Thermal engine using noncombustible fuels for powering transport vehicles and other uses

ABSTRACT

A thermal engine includes an expansion fluid pump which propels water from an expansion fluid tank into an electrolytic cell having an anode and a cathode, which generates a quantity of oxyhydrogen from the water; and propels the oxyhydrogen into one of an engine cylinder and an exhaust chamber, whereupon oxyhydrogen propelled into the cylinder expands abruptly into steam in the intake chamber to increase pressure within the cylinder and thereby enhance thermal engine power, and oxyhydrogen propelled into the heat exchanger cools the water vapor back into liquid water, which generates a vacuum within the exhaust chamber to increase the power of the thermal engine.

FILING HISTORY

This application is a continuation-in-part of application Ser. No. 13/506,943 filed on May 25, 2012, which is a continuation-in-part of application Ser. No. 12/380,626, filed on Mar. 2, 2009, issuing into U.S. Pat. No. 8,186,160 on May 29, 2012.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to the field of engines that convert thermal energy into mechanical energy. More specifically the present invention relates to a thermal engine such as for powering a vehicle, and preferably a train or a motorcycle, including a cylinder and a piston having a piston head and a piston crank and an insulated thermal battery including at least a thermal mass such as a metal block for storing and retaining heat to cause expansion fluid to expand inside the a cylinder expansion chamber between the cylinder head and the piston head to drive a crankshaft.

In its most basic form, as mentioned above generally, the thermal engine incorporates several conventional engine elements including an engine valve block cover sealingly mated to an engine valve block which is sealingly mated to an engine block which in turn is sealingly mated to an oil sump. The engine block has a cylinder chamber within which a piston head is slidably and sealingly retained to form a variable volume cylinder expansion chamber between a piston head and the engine valve block, said engine valve block having a intake valve port with a intake valve and having an exhaust valve port with an exhaust valve; the intake valve port being fluidly connected to an intake chamber within the valve cover for receiving expanded fluid from the thermal battery, said exhaust valve port being fluidly connected to an exhaust chamber for removal of exhausted expanded fluid; a crankshaft mechanically linked to the piston head opposite the engine valve block by a piston crank, a cylinder valve operating means preferably comprising a cam shaft and cams mounted thereon, said cam shaft preferably driven by the torque of a drive shaft. The engine further comprises a coolant pump and a coolant radiator for circulating engine coolant through the engine block for cooling the engine such as a mixture of ethylene glycol and water; an engine starting means connected to the drive shaft; a thermal battery consisting of a contiguous thermal battery vacuum case within which is contained a sealed thermal mass chamber for storing a thermal mass, a heat transfer fluid chamber in fluid communication with the thermal mass chamber. The engine further comprises an expansion fluid tank and an expansion chamber; an expansion fluid pump for delivering expansion fluid from the expansion fluid tank into the expansion chamber; a heat transfer fluid blower in fluid communication with the heat transfer fluid chamber for blowing a heat transfer fluid such as air through said thermal mass chamber for uniform heat removal and transporting said heat transfer fluid to an expansion chamber; the expansion chamber receiving expansion fluid from the expansion fluid pump to circulate therein and receive heat from the heat transfer fluid through the heat transfer fluid passageways within said expansion chamber, to uniformly heat and expand expansion fluid, from a liquid phase to an expanded fluid in the vapor phase to transmit and accumulate pressurized expanded fluid vapor into the intake chamber. As a result, when the engine starting means turns the drive shaft, the expansion fluid pump delivers a quantity of expansion fluid into the expansion chamber, and further, the heat transfer fluid blower blows heat transfer fluid through the thermal mass chamber to receive heat from the thermal mass and transport it to heat transfer fluid passageways in the expansion chamber to exchange said heat with the expansion fluid and causing expansion fluid to expand into a vapor and become expanded fluid. When the piston head is at top dead center of the cylinder chamber a cylinder valve operating means opens the intake valve and expanded fluid vapor is passed through the intake valve port into the cylinder expansion chamber to generate pressure and drive the piston head from top dead center to bottom dead center. The piston head motion generates a force transmitted by the piston crank to turn the crankshaft and generate mechanical power using the thermodynamic potential of the expanded fluid vapor, so that when the piston head is at bottom dead center the drive force generated on the drive shaft causes cylinder valve operating means to close the intake valve and to open the exhaust valve and causes expanded fluid vapor to exit through exhaust valve port into the exhaust chamber for removal of exhaust expanded fluid as the piston head rises to top dead center passing expanded fluid vapor into a first heat exchanger path to exchange heat with the engine coolant passing through a hydraulically separate second heat exchanger path in the heat exchanger so that the engine coolant receives heat and cools and condenses the expanded fluid vapor back into expansion fluid and to advantageously generate a negative vapor pressure to assist and pull the piston head back to top dead center to repeat the cycle. A flow check valve on the heat exchanger output prevents back flow of condensate to maintain a negative pressure. The thermal engine further includes an expansion fluid tank to receive condensed expansion fluid from the heat exchanger, an expansion fluid pump for pumping expansion fluid from the expansion fluid tank back into the thermal mass expansion fluid passageways to repeat the process.

The cylinder valves include an intake valve fluidly connected to the cylinder expansion chamber of the engine to control the flow of expanded fluid into the cylinder expansion chamber and an exhaust valve fluidly connected to the cylinder expansion chamber of the engine to control the flow of expanded fluid out of the cylinder expansion chamber. A cylinder valve operating means preferably includes a camshaft and push rods and alternatively an electronic solenoid cylinder valve actuation means. In the case when a camshaft is used, the intake and valve exhaust valve ride on cams along the camshaft which forces them to open and close against a cam spring compression force in a conventional fashion of existing engines; and alternatively an electronic solenoid cylinder valve actuation means may be used without a cam shaft to electronically operate the intake valve and the exhaust valve in a cyclic sequence that is in phase with the positions of the pistons in relation to the cylinder expansion chamber. A flywheel is attached to the drive shaft connected to one end of the crankshaft preferably extends out of the crankcase through a shaft port to transmit the thermal engine power in the form of torque to any desired mechanical load such as a vehicle.

In the closed cycle format of the invention, the expansion fluid delivery means preferably is an expansion fluid pump or simply gravity in the case of a small engine. In the case of an open cycle format of the present invention, the expansion fluid delivery means alternatively consists of pressurizing the expansion fluid tank to pump out expansion fluid into the expansion fluid passageways by pressure. In the closed cycle format, no expansion fluid is lost and the same quantity of expansion fluid remains in the engine cycle in vapor and liquid phase and is reused over and over again by means of condensation. In the case of an open cycle format the expanded fluid is exhausted into the atmosphere.

In general operation of the closed cycle engine, heat is generated and stored in the thermal mass by one of several means. The first preferred means is by passing electric current through resistive heating elements embedded in the thermal mass for a period of time and the second alternative means is by imposing radiation heater elements such as from infrared heating elements embedded in the thermal mass, and the third preferred means is by using an electric current to electrolyze water to generate Hydrogen and Oxygen within a water stream which are then combusted inside the thermal mass to generate heat. The fifth preferred means is by using electromagnetic induction heating means on the thermal mass for a period of time, and the fourth preferred means is by using a radiative element such as thorium to continuously heat the thermal mass.

The thermal engine is started by switching on an electric engine starter and alternatively by turning on an expansion fluid pump and switching on the heat transfer blower by means of an electronic ignition switch which pumps a quantity of expansion fluid from an expansion fluid tank through a bypass control valve and then through a flow regulator. The bypass control valve allows a predetermine amount of the expansion fluid to flow through a flow regulator and then into the expansion fluid passageways while bypassing excess expansion fluid back to an expansion fluid storage tank. The heat transfer fluid blower blows heat transfer fluid such as air or helium through the thermal mass chamber to receive heat from the thermal mass and transport said heated heat transfer fluid into the heat transfer fluid passageways in the expansion chamber and to exchange heat with the expansion fluid.

The flow regulator allows only the prescribed amount of expansion fluid to pass into the expansion fluid passageways and the heat stored in the heat transfer fluid from the thermal mass causes expansion fluid to expand by a phase change into expanded fluid to generate pressure in the intake chamber. The turning of the crankshaft causes the piston head to move and when it rises to top dead center, the cylinder valve operating means causes the intake valve to an open while causing the exhaust valve to close. The pressurized expanded fluid in the intake chamber rushes through intake valve port into the cylinder expansion chamber and pushes the piston head to bottom dead center position turning the crankshaft and thereby causing cylinder valve operating means to close the intake valve and also open the exhaust valve causing the piston head to return to top dead center position using the momentum stored in a flywheel and allowing the expanded fluid to exit the cylinder expansion chamber into the exhaust chamber through exhaust valve port.

In the closed cycle format, the expanded fluid exhausted from the exhaust port of the engine is transported through the open exhaust valve through an exhaust tube to an engine radiator to be cooled by a radiator fan. The cooler expansion fluid and any expanded fluid remaining as gas is then passed through a first heat exchanger path in a heat exchanger and at the same time the recirculate expansion fluid is passed through is passed through a second heat exchanger path in the heat exchanger that is in maximal thermal contact with the first heat exchanger path to exchange heat and cool the expanded fluid back to expansion fluid. Alternatively air can be used to blow through the second heat exchanger path in the heat exchanger to exchange heat and cool the expanded fluid and expansion fluid mixture back to expansion fluid. Thus the expansion fluid can act as coolant to remove and recover heat from the expanded fluid and use the heat thus removed to reheat the expansion fluid to keep it at an operating temperature close to the boiling point. Advantageously, a radiator fan may be driven by the engine crank shaft and alternatively by an electric motor to remove heat from the engine radiator by means of passing air through the engine radiator fins and directing said air back over the engine block to reheat the engine block to a temperature close to the boiling point of the expansion fluid. Thus very little heat from the thermal battery is lost to atmosphere.

In the open cycle format of the invention the expanded fluid may be exhausted directly to atmosphere from the exhaust tube. In the closed format of the invention, the heat exchanger cools the expanded fluid vapor back into expansion fluid and a check valve at the end of the exhaust tube generates a vacuum within the exhaust chamber to increase the power of the thermal engine since when the exhaust valve port opens the negative pressure in the cylinder expansion chamber will, in addition to the energy stored in the flywheel, cause the piston head to rapidly return by negative pressure to top dead center position. This adds more power to the thermal engine since the invention essentially teaches the use of expansion fluid in both its pressurized vapor expanded fluid form and its vacuum condensate state to push and return the piston head from top dead center position to bottom dead center position and back to top dead center position. This vacuum assistance is possible in both the open cycle format and the closed cycle format if the exhausted expanded fluid is passed through a long enough exhaust tube before being exhausted to atmosphere. In such a case, the rapid cooling of the expanded fluid in the exhaust tube causes the expanded fluid to undergo a phase change from the vapor phase to the liquid phase and such rapid condensation results in a vacuum being generated momentarily in the exhaust chamber. Thus, by adjusting the amount of heat exchanger area and capacity and the length of the exhaust tube, it is possible to regulate the timing of the vacuum formed with the motion of the piston head as moves from top dead position center to bottom dead center position and then back to top dead center position.

In the closed cycle format of the invention, an expansion fluid pump pumps a pressurized quantity of expansion fluid from an expansion fluid tank through an excess bypass control valve and then through a flow regulator. The bypass control valve allows a predetermine amount of the expansion fluid to flow through the flow regulator into the expansion fluid passageways of the thermal mass while bypassing excess expansion fluid as recirculate expansion fluid through the second heat exchanger path and then back to an expansion fluid storage tank. The flow regulator allows only the prescribed amount of expansion fluid to pass into the expansion fluid passageways to expand by a phase change into expanded fluid to generate pressure when the thermal mass exchanges heat with the expansion fluid within the thermal mass. This pressure is then transmitted into the intake chamber. Advantageously, the flow regulator can be mechanically actuated by a manually actuated pedal to open or close the flow regulator and allow the variation of the quantity of expansion fluid that is fed as fuel into the expansion fluid passageways. Since the flow regulator determines the amount of expanded fluid that will be generated by the thermal mass, regulating the bypass control valve determines the power of the engine. When the piston head is at top dead center of the cylinder chamber the intake cam shaft rotates such that a cam opens the intake valve and expanded fluid vapor is passed through the intake valve port into the cylinder expansion chamber to generate pressure and drive the piston head from top dead center to bottom dead center, and the piston head motion generates a force transmitted by the piston crank to turn the crankshaft and generate mechanical power using the thermodynamic potential of the expanded fluid vapor; and when the piston head is at bottom dead center the cylinder valve operating means closes intake valve closes and at the same time opens the exhaust valve to cause expanded fluid vapor to exit through exhaust valve port into the exhaust chamber for removal of exhaust expanded fluid as the piston head rises to top dead center again causing expanded fluid vapor to enter into the radiator through the exhaust tube through a check valve and then into the first heat exchanger path to exchange heat with either recirculate expansion fluid or alternatively air passing through a second heat exchanger path and to cool and condense the expanded fluid vapor back into expansion fluid and to advantageously generate a negative vapor pressure to assist and pull the piston head back to top dead center to repeat the cycle. Alternatively in the open cycle form, the expanded fluid can exit the cylinder expansion chamber through the exhaust tube to bypass the heat exchanger and be expelled directly to atmosphere. The piston head freely returns to top dead center by the continued angular momentum, the rotation of the crankshaft and flywheel and allowing the remaining elements of the expanded fluid out of the cylinder into the exhaust chamber to cool and generate a negative pressure of vapor condensation so that the cycle can continuously repeat until stopped. To stop the cycle, the expansion fluid pump is simply cut off and the flow to the flow regulator is simply closed off to stop the flow of expansion fluid into the expansion chamber.

At close to bottom dead center the turning of the crankshaft, the momentum stored in the flywheel, and the negative pressure of vapor condensation causes the piston head to rapidly move back towards top dead center to repeat the cycle and to causes the intake valve to close while causing the exhaust valve to open to repeat the cycle. Advantageously, the recirculate expansion fluid is pumped through a first heat exchanger path to absorb otherwise wasted heat directly from the expanded fluid by exchanging heat with air or as it exits the expansion cylinder. This allows unused heat from the expanded fluid to be absorbed by the expansion fluid and recirculate expansion fluid before expansion fluid renters the thermal battery and before the recirculate expansion fluid is returned to the expansion fluid storage tank. The recirculate expansion fluid can be mixed in with the expanded fluid within the exhaust tube so that their mingling will condense the expanded fluid rapidly back to expansion fluid. Alternatively, the recirculate expansion fluid can be passed through a condensate return tube channeled through the interior of the exhaust tube to exchange heat with the expanded fluid and then removed from the exhaust tube and taken to the expansion fluid storage tank. Further, condensate expansion fluid from condensed expanded fluid inside the exhaust tube can be removed by means of a vapor trap such as a steam trap to be pumped to rejoin the expansion fluid in the expansion fluid storage tank.

If more heat needs to be removed from the expanded fluid in the exhaust tube, then a separate path for an engine coolant can also be passed through the interior of the exhaust tube to allow an engine coolant to absorb more heat from the expanded fluid.

The condensate and recirculate expansion fluid are combined and transported to the expansion fluid storage tank to be reused again. The surface area of the heat exchanger is substantial and it is calculated to be sufficient to condense the exhausted expanded fluid before it exist the heat exchanger. The engine coolant is pumped to the engine block to reheat the engine block.

Unlike conventional engines that require heat to be removed from the engine block, the present invention admits to reusing the engine coolant thermal energy to reheat the engine block. The engine coolant is pumped by a coolant pump through the heat exchanger and then through the engine block, then through the engine radiator, to remove heat from the engine coolant and use the heat thus removed to reheat the engine block to keep it at an operating temperature substantially close to the boiling point of the expansion fluid. Advantageously, a radiator fan may be driven by either the electric power from a battery or by means of the engine crank shaft to remove heat from the engine radiator by passing air through the engine radiator fins and directing said air back over the engine block to reheat the engine block to a temperature substantially close to the boiling point of the expansion fluid. It is important that the radiator fan speed and air CFM capacity be properly specified to just remove heat from the radiator and impose and distribute said heat unto the engine block and not necessarily to cool the engine block. Thus the radiator fan must be specified with a thermostat that activates the fan only when the engine coolant temperature is close to the boiling point of the expansion fluid. Thus minimal heat from the thermal battery is lost as wasted heat to atmosphere during the operation of the engine. A negative pressure will be generated inside the heat exchanger by the rapid condensation of the expanded fluid back to expansion fluid and caution must be exercised to make sure that the fluid circuits and the heat exchanger can handle a negative atmospheric pressure.

Advantageously, the recirculate expansion fluid could be directly sprayed inside of the exhaust tube to mingle and condense the flowing expanded fluid into its liquid form again. This ensures maximum use of the heat wasted from the exhausted expanded fluid from the engine. The condensed expansion fluid, expanded fluid and the recirculate expansion fluid could also be returned together through the heat exchanger for further condensation of expanded fluid. The condensate and the expansion fluid thus obtained can then be recirculated as recirculate expansion fluid back to the expansion fluid storage tank.

In the case of a vehicle such as a car, the flow regulator is controlled by a foot pedal and cabling or by electronic means to regulate the amount of expansion fluid that is fed to the expansion chamber for expansion. This in turns regulates the power of the engine. Generally, an electric expansion fluid pump is used to cut-off the flow completely when the ignition is turned off and the engine power is turned off. During normal operation, the bypass valve and flow regulator are designed to have a minimum pass through for the expansion fluid so that the engine can idle at low speeds.

A pressure sensor attached to read the pressure of the expanded fluid in the expansion chamber can be used to sense the pressure of the expanded fluid in the expansion chamber to cutoff the flow of expansion fluid from the expansion fluid pump to maintain the pressure of the expanded fluid at a preset maximum value and to turn on the flow from of expansion fluid pump to maintain the pressure of the expanded fluid at a preset minimum and maximum pressure.

Further, the thermal battery has a temperature sensor and charge regulator for controlling the thermal mass heating means and thus control the temperature of the maximum and minimum temperature-charge of the thermal mass.

In the case when the thermal battery is used in an electric train for example, electricity can be charged into the thermal mass heating means of the thermal mass through conventional electric tracks so that the thermal mass can continuously be heated during operation. In the case of road vehicles, it is possible to place induction chargers directly beneath the road to directly recharge the thermal mass during motion as the vehicle passes over the induction chargers. It is important that thermal blankets and other means be used to prevent loss of heat from the entire engine block, the thermal battery and the expansion fluid tank and other heated parts such as the exhaust tube.

In one form of the invention, the expansion fluid is an electrolyte such as water. An expansion fluid pump pumps a pressurized quantity of expansion fluid from an expansion fluid tank through an excess bypass control valve and then through a flow regulator. The bypass control valve allows a predetermined amount of the expansion fluid to flow through the flow regulator into the expansion fluid passageways of the thermal mass while bypassing excess expansion fluid as recirculate expansion fluid through the second heat exchanger path and then back to an expansion fluid storage tank. The flow regulator allows only the prescribed amount of expansion fluid to pass through an electrolysis chamber before it enters the thermal mass passageways. An electric current is used to generate Oxyhydrogen, a mixture of hydrogen (H₂) and oxygen (O₂) gases within the electrolyzer therein. Oxyhydrogen is also sometimes referred to as Brown gas or HHO. While it is known that Oxyhydrogen gas can explode to form steam when at the stoichiometric ratio of its components oxygen and hydrogen, it can also implode to form water. However, no prior art describes how to cause the Oxyhydrogen gas to remain as autoignited steam for use as a power generator. A lot of literature has been published on the phenomena of heat and explosion generation from Oxyhydrogen gas. However, the present inventor has investigated the claims made for the use of Oxyhydrogen gas as an over unity power generation means and found them to be false. The amount of energy used remains constant with the amount of energy it generates. However if one considers that a given volume of the gas can be reduced to about

$\frac{1}{1400}$

times its original volume, then one can generate either pressure or a vacuum using the gas. In theory, Oxyhydrogen, is a gas and not steam. Since steam expands to about 1400 times its volume as water, Oxyhydrogen gas will expand when there is no thermal energy loss and when it is ignited by the heat of reaction δE that goes to form steam from water molecules. All its thermal energy comes from ignition reaction

H₂+2O₂→2H₂O+δE

Thus the formation of a dry gas form of Oxyhydrogen formed within a fluid matrix generates a gas as opposed to steam. If this gas is then subjected to high temperatures from a spark or from a thermal mass it will ignite and form steam instead of water. Thus it can explode to 1400 times its volume when subjected to temperatures greater than its phase change temperature. That is why a spark or a flame which is above the phase change temperature can ignite the gas and cause it to explode. It is a very efficient way to use any energy source above the phase change temperature to convert expansion fluid to expanded fluid. However it accords no magic or over unity energy.

In the presence of a heat absorber however, the heat removed from the Oxyhydrogen when ignited can immediately re-condense any local steam thus formed by the reaction resulting in an implosion to water. Thus it is important that the Oxyhydrogen gas thus generated by electrolysis of the expansion fluid be contained as bubbles within the flowing expanded fluid that enters into the thermal battery and that the heat caused by the reaction not be removed from. An electrolytic cell uses electricity from a battery to split the expansion fluid (water in this case) into hydrogen and oxygen. When molecules of this gas are ignited by either a heat source of a spark above the phase temperature of the expansion fluid, they form steam since the reaction has no time to condense the steam and the heat SE thus generated can cause the water thus formed to explode to 1800 times its volume as steam. Heat generated by this explosion within the thermal passageways adds to the heat from thermal mass by means of an electric power source. No additional energy is gained when one considers that the source of the heat is from a battery. However it is a means of very efficiently and continuously converting an electric energy source to thermal energy in the thermal engine. It is thus important that the Oxyhydrogen gas be subjected to temperatures much higher than 500° F. to autoignite and explode and remain as steam.

The Oxyhydrogen thus generated must be encapsulated as bubbles within the expansion fluid and when in contact with the thermal mass and will auto ignite and generate additional pressure as it converts to expanded fluid within the hot thermal battery. In this form of the invention, the electrolysis can be performed within the flow stream of expansion fluid that is channeled into the thermal mass to gain heat from an electric current without introducing any additional heating elements except for a battery. It is like direct heating of the expansion fluid using an electric current.

In this form of the invention, the electrolysis can be performed by a series of metallic anodes and cathodes that are sealingly within the flow stream of expansion fluid that is channeled into the thermal battery expansion passageways.

In yet a very innovative and inventive manner, the Oxyhydrogen gas can be generated by electrolysis in a cooler than temperature than the phase change temperature of the expansion fluid. This can be done within the recirculate expansion fluid and then removed therefrom and directed into the first heat exchanger passageways where the expanded fluid is being cooled to expansion fluid below the phase change temperature. In this case the Oxyhydrogen gas will immediately implode to about

$\frac{1}{1800}$

times its original volume. The implosion is a result of the gas thus formed reducing in volume back to a fluid phase from a gas phase. However, it is important that the electrolysis be done at an electrode temperature higher than the phase change temperature of the expansion fluid. My investigation shows that when the current to the electrodes exceeds the electrolytic capacity of the electrodes, the local extra energy from the electrodes cause the phase change temperature of the Oxyhydrogen and it is immediately form as steam (already expanded gas). Thus when this steam is cooled at the heat exchanger, one can generate a tremendous vacuum within the exhaust tube that acts within the exhaust chamber. Thus one can effectuate the exhaust stroke and cause a negative vacuum pressure to occur while the piston is rising from Bottom dead center to increase the power of the engine. Thus the electrolysis of water, or any electrolyte can be used to power the engine both in a positive pressure form at the intake and as a negative pressure form at the exhaust.

2. Description of the Prior Art

So-called gas and combustible fluid engines are known that can operate with different types of fuels and are based on certain thermodynamic principles, such as the Diesel, Carnot, Rankine, and Otto cycles. In combustion engines an air-fuel mixture is compressed and then ignited. The compression results in an expansion of gases within the cylinder chamber, pushing a piston slidably retained within the cylinder in a repeated cycle to turn a crank shaft and so to generate mechanical power from the fuel. The current prior art engines therefore rely on combustible fuels that cause global pollution and health associated problems. In an effort to reduce the pollution and dependence on fossil fuels, several types of engines have been invented including electrically powered vehicles which rely on the storage of electric power in batteries.

While these vehicles are of current interest, a growing concern about the disposal of chemical batteries and the efficient global transformation of these new technologies to replace existing technologies has emerged. What is needed is a thermal engine design which adopts a philosophy of replacing or assisting existing technologies such as fossil fuel combustion engines and electric battery powered vehicles. Such a thermal engine as described by the present invention uses thermally generated power in a closed or open thermodynamic cycle to generate power without pollution. It also can be used in conjunction with conventional engines to improve their efficiencies without substantial change to current engine manufacturing technology.

It is thus an object of the present invention to provide an engine which can be operated with non-combustible expansion fluids which do not combust and which uses a phase change to expand a fluid from a liquid phase to a vapor phase and generate power thereby achieve a high degree of efficiency during operation. An engine of this kind, in accordance with the invention, can be optimized by its geometry through maximizing the thermal mass and minimizing the surface area of the thermal battery for storing a maximum amount of thermal energy in the form of a direct heat. Without limiting the scope of the invention, however, the preferred mode of operation is in a pure thermal mode where the thermal battery is simply a thermal mass consisting of a preferably stainless steel allows and ceramic composite and alternatively other metal allows and molten salts that have high thermal storage capacity.

It is another object of the present invention to provide and thermal battery which can be used in conjunction with a molten electrolytic salt contained within the battery as a thermal mass to store heat.

It is still another object of the present invention to provide an engine in which pressure generated when vapor expands from a liquid state can then be used as a vapor powered engine, whereof, a liquid such as water is injected into the thermal mass of the engine to generate pressurized steam as an expanded fluid to generate power.

Advantageously, much more energy can be stored in such a thermal battery than in a conventional electric battery of the same weight since the thermal storage capacity of a regular chemical battery far exceeds its electric storage energy. It is in fact the preferred means that Nature has chosen to store energy in stars and gravitating bodies.

Advantageously, such a thermal battery powered engine can be equipped with an expansion fluid condensation radiator to generate addition negative pressure within the cylinder during the exhaust cycle to increase the power of the engine.

Since the closed system does not lose any expansion fluid to atmosphere, the thermal expansion fluid can be chosen from any thermodynamic fluid such as a refrigerant that has suitable properties. Water, HFE7000, HFC134a and other refrigerants can be used.

It is a further objective of the present invention to disclose a thermal engine that is powered by a thermal battery causing a phase change in an expansion fluid from a liquid phase to a vapor phase.

It is yet another objective of the invention to use an electrolytic cell to generate Oxyhydrogen as steam as a means of conversion of electric energy to steam for powering a thermal engine with pressure with little or no energy loss.

It is yet another objective of the present invention to use an electrolytic cell to generate Oxyhydrogen as steam to convert electric energy into a vacuum source to power a thermal engine by means of a vacuum.

It is a further objective of the present invention to disclose a thermal engine that can be operated in a closed cycle without any exhaust and that reuses a fixed amount of expansion fluid in a closed cycle that undergoes a phase change from a liquid to a vapor to do thermodynamic work and then back to a liquid phase to be reused in a continuous fashion.

It is a further objective of the present invention to disclose a thermal engine that can be operated in an open cycle that uses an indefinite amount of water as an expansion fluid that undergoes a phase change to steam to do thermodynamic work and that can be exhausted to atmosphere without causing pollution.

It is a further objective of the present invention to disclose a thermal engine that can be recharged by means of electric thermal heating means over a period of time to store energy in a thermal battery.

It is a further objective of the present invention to disclose a thermal engine that can be rapidly recharged by means of electromagnetic induction heating over a period of time to store energy in a thermal battery. Advantageously such an electromagnetic induction charging system can be non-invasive and thus in the case when the thermal engine is used in a vehicle, the vehicle would simply slowly pass over such an inductor placed alongside or under the road and gets charged without having to stop.

It is a further objective of this invention to provide an engine wherein the thermal mass energy can be isolated away from the expansion chamber by means of a heat transfer fluid.

It is finally an object of the present invention to provide an engine which is highly efficient and easy to operate and environmentally friendly. Advantageously the thermal battery can be made from recyclable materials that have no adverse environmental effects.

Advantageously, unlike electric batteries whose potential deteriorates with the number of charges, the thermal battery can be recharged with heat a large number of times without reducing its capacity to store heat energy, and without deterioration. Further, the thermal battery is environmentally safe and can be reused to manufacture new items by recycling its material without any consequences to the environment.

Further, in an open cycle embodiment of the present invention, the exhaust of the engine using a thermal battery can be pure water or steam. In a closed cycle format embodiment of the present invention, any refrigerant fluid that has suitable thermodynamic properties can be used since the exhausted condensate of the expanded fluid is recaptured from the engine and recycled, and such an engine would need very little expansion fluid to operate in a closed system and no emissions would result.

SUMMARY OF THE INVENTION

The present invention accomplishes the above-stated objectives, as well as others, as may be determined by a fair reading and interpretation of the entire specification.

The present invention relates generally to the field of engines that convert heat into mechanical energy. More specifically the present invention relates to a thermal engine such as for powering a vehicle, a train or other devices, including a cylinder and a piston having a piston head and a piston crank and an insulated thermal battery including at least a thermal mass such as a metal block for storing and retaining heat to cause expansion fluid to expand inside the a cylinder expansion chamber between the cylinder head and the piston head to drive a crankshaft.

Since the anticipated operating temperature of the thermal expansion fluid depends on it boiling point, except for the thermal battery, the remaining thermal engine can be constructed from durable materials such as aluminum and a suitable plastic material such as polypropylene or peek. In its most basic form, as mentioned above generally, the thermal engine incorporates several conventional engine elements including valve cover sealingly mated to a valve block sealingly mated to an engine block with a crank case that is sealingly mated to a sump. These components of the thermal engine could be injection molded from suitable plastics and then lined with stainless steel inserts in areas where wear might be a problem.

The engine block has one or more longitudinal spaced cylinder chambers bored through it with axes perpendicular to its open face within each of which a piston head is slidably and sealingly retained to form a variable volume cylinder expansion chamber between the piston head and the valve block. The other end of the engine block is sealingly connected to thin walled crankcase. The anticipated operating temperature of the engine block, the valve cover, the valve block, the crankcase, the sump and the piston head is below the melt point of most plastics and so these components could be constructed from durable materials such as aluminum allows, plastics such as Peek, Vespel® SP-1 Polyimide, Meldin® 7001 Polyimide, Kapton® Polyimide, Kaptrex® Polyimide, Torlon® 4203, Vestakeep® PEEK, CeramaPEEK®, Ryton®—PPS—40% Glass-Filled and Celazole® PBI. Celazole® PBI offers the highest heat resistance and mechanical property retention over 400° F. well above the boiling point of water. The cylinder chamber could be lined with stainless steel sleeves to prevent wear due to the sliding motion of the piston head. The piston head has piston rings that form an adequate slide seal with the cylinder chamber. A crankshaft is mechanically linked to the piston head opposite the valve block by a piston crank.

The valve block has intake valve ports with intake valves and the same number of exhaust valve ports with exhaust valves for fluid communication with the cylinder chambers in the engine block; the valve cover sealing forms an intake chamber and an exhaust chamber over the intake valve port and the exhaust valve ports respectively. The intake chamber is fluidly connected to receive expanded fluid through an intake tube from a thermal battery; the exhaust chamber is fluidly connected to an exhaust tube at the end of which is a check valve that only allows exhaust expanded fluid from the exhaust chamber to exit the exhaust tube. A heat exchanger may be optionally placed after the check valve to cool and condense exhausted vapor from the exhaust chamber using an engine coolant and an engine radiator. A thermal battery consisting of a contiguous thermal battery vacuum case within which is contained a sealed thermal mass chamber for storing a thermal mass, a heat transfer fluid chamber in fluid communication with the thermal mass chamber. The thermal mass chamber surrounds the thermal mass and the thermal battery vacuum case surrounds the thermal mass chamber so that a vacuum can be pulled in the thermal battery vacuum case to surround the thermal mass chamber and insulate it from convective heat loss. Sealed heat transfer fluid passageways fluidly connect the thermal mass chamber to a heat transfer fluid blower to circulate heat transfer fluid such as air within and through the thermal mass chamber for uniform heat removal and transporting said heat transfer fluid to an expansion chamber remotely located from the thermal battery vacuum case. The heat transfer fluid passageways sealingly pass through the walls of the thermal battery vacuum case and fluidly and sealingly connect to the thermal mass chamber to continuously circulate heat transfer fluid through and between the expansion chamber and through and between the thermal mass chamber without introducing any heat transfer fluid into the thermal battery vacuum chamber. Thus the integrity of the vacuum within the thermal battery vacuum chamber that surrounds the thermal mass chamber is maintained. The thermal battery vacuum chamber, the thermal mass, the thermal mass chamber, the heat transfer fluid passageways and the expansion chamber must all be constructed from durable high melting point materials such as stainless steel, titanium or ceramics. The heat transfer fluid passageways are preferably tubes of suitable diameter for easy flowing of the heat transfer fluid by means the heat transfer fluid blower and can be welded through the walls of the thermal battery vacuum case to sealing and fluidly communicate with the thermal mass chamber and the expansion chamber. Advantageously, the expansion chamber can be located a distance away from the thermal battery itself and still effectuate the expansion of expansion fluid to expanded fluid using heat transferred by the heat transfer fluid from the thermal mass. The expansion chamber receives expansion fluid from an expansion fluid pump to circulate therein and exchange heat from the heat transfer fluid through the heat transfer fluid passageways within said expansion chamber to uniformly heat and expand expansion fluid from a liquid phase to an expanded fluid in the vapor phase to transmit and accumulate pressurized expanded fluid vapor into the intake chamber of the engine so that when the engine starting means turns the drive shaft, the expansion fluid pump delivers a quantity of expansion fluid into the expansion chamber, and further, the heat transfer fluid blower blows heat transfer fluid through the thermal mass chamber to receive heat from the thermal mass and transport it to heat transfer fluid passageways in the expansion chamber to exchange said heat with the expansion fluid and causing expansion fluid to expand into a vapor and become expanded fluid, and when the piston head is at top dead center of the cylinder chamber a cylinder valve operating means opens the intake valve and expanded fluid vapor is passed through the intake valve port into the cylinder expansion chamber to generate pressure and drive the piston head from top dead center to bottom dead center, the piston head motion generating a force transmitted by the piston crank to turn the crankshaft and generate mechanical power using the thermodynamic potential of the expanded fluid vapor, so that when the piston head is at bottom dead center the drive force generated on the drive shaft causes cylinder valve operating means to close the intake valve and to open the exhaust valve and cause expanded fluid vapor to exit through exhaust valve port into the exhaust chamber for removal of exhaust expanded fluid as the piston head rises to top dead center passing expanded fluid vapor into a first heat exchanger path to exchange heat with the engine coolant passing through a hydraulically separate second heat exchanger path in the heat exchanger so that the engine coolant receives heat and cools and condenses the expanded fluid vapor back into expansion fluid and to advantageously generate a negative vapor pressure to assist and pull the piston head back to top dead center to repeat the cycle; a flow check valve on the heat exchanger output prevents back flow of condensate to maintain a negative pressure; an expansion fluid tank to receive condensed expansion fluid from the heat exchanger, an expansion fluid pump for pumping expansion fluid from the expansion fluid tank back into the expansion chamber to exchange heat with the heat transfer fluid through the heat transfer fluid passageways and then to repeat the process.

The thermal battery vacuum case must be made from heat resistant and low expansion materials such as ceramics and metal allows. It cannot be made from plastic or aluminum since it must withstand very high temperatures.

In a conventional engine form, an exhaust cam shaft is axially positioned inside the exhaust chamber with a cam mounted thereon above each exhaust valve. In regular gas engines, the intake valves are designed to open up when subjected to negative pressure within the cylinder expansion chamber. They are generally only subjected to no more than atmospheric pressure or super charger pressures. This allows gas and air mixtures to be aspirated into the cylinder expansion chamber. In this invention however, the intake valves are designed to maintain a seal under high pressure and cannot be opened up by negative cylinder expansion chamber pressures. The intake valve can only be opened by the action of an intake cam shaft pushing the intake valve open. Both the intake valve and the exhaust valve must be actuated by cams and not by aspiration or negative pressures. Advantageously, both the intake valve and the exhaust valve form a positive seal under any pressure.

An intake cam shaft is axially positioned inside the intake chamber with a cam mounted thereon above each intake valve. Both cam shafts are suitably mechanically attached by a drive belt or gear system to a drive shaft at the end of the crankshaft. An engine starter is also connected to drive shaft to rotate the drive shaft when the thermal engine is started. In an electronic cylinder valve format, electric solenoids could be used to exactly open and close the intake and exhaust valves in phase with the engine cycle.

The thermal engine further comprises an expansion fluid pump for pumping expansion fluid into the expansion chamber. The heat from the thermal mass is transported by the heat transfer fluid into the expansion chamber by the expansion fluid pump which delivers a quantity of expansion fluid into the expansion chamber, and further, the heat transfer fluid blower blows heat transfer fluid through the thermal mass chamber to receive heat from the thermal mass and transport it through heat transfer fluid passageways in the expansion chamber. Thus when the expansion fluid pump pumps expansion fluid into the expansion chamber the heat from the heat transfer fluid causes expansion fluid to expand into a vapor and become expanded fluid. The expansion chamber is fluidly connected to the intake chamber of the engine.

Expansion fluid flow is regulated to divide into two paths with one path entering the into the expansion chamber to exchange heat with the heat transfer fluid and to expand into expanded fluid, then flowing expanded fluid into the intake chamber then flowing expanded fluid to the intake valve ports, which if open will have fluid communication with the cylinder expansion chamber and the pressure of expanded fluid will cause the piston head to move and then fluidly communicate expansion fluid through the exhaust valve port, which if open will fluidly communicate through the exhaust tube and through the check valve with either atmosphere when an open cycle design is used, or with one path through a heat exchanger where it is condensed back to expansion fluid and then passed through the suction of the expansion fluid pump back to the expansion fluid tank, then finally back to the expansion chamber to re-expand and repeat the cycle.

The second path from the bypass valve passes some of the expansion fluid as recirculate expansion fluid in a recirculate tube that passes through the interior of the exhaust tube to exchange and absorb some more heat from the expanded fluid and help cool expanded fluid in the exhaust tube; then passing expanded fluid and any condensed expansion fluid through a one path of a heat exchanger to exchange heat with another separate path of the heat exchanger; through which engine coolant is passed to exchange heat with the expanded fluid and condense all the expanded fluid back to expansion fluid; then passing to the suction of the expansion fluid pump to be pumped back as expansion fluid to the expansion fluid tank to repeat the cycle.

The recirculate tube passing through the interior of the exhaust tube is preferably made from heat conductive materials such as finned aluminum tubing to allow maximum loss of heat to the recirculate expansion fluid. This way most of the heat from the expanded fluid is reabsorbed back into the recirculate expansion fluid and not lost to atmosphere before it returns to the expansion fluid tank to repeat the cycle. It is advantageous to insulate the exhaust tube so that very little heat is lost to atmosphere. Most of the heat from the expanded fluid should be absorbed by the engine coolant and by the expansion fluid so that it can be reused as thermal energy in the engine. The area of the heat exchanger is substantial and it is calculated to suffice to condense the exhausted expanded fluid before it exist the heat exchanger. The engine coolant is pumped by the engine coolant pump and circulated back through the engine block and then through a radiator. The engine coolant is pumped to the engine block to reheat the engine block and further heat is removed from the engine coolant by means of a radiator fan that blows air through the radiator to remove the heat of condensation from the engine coolant and reheat the outer perimeter of the engine block. It is advisable to insulate the entire engine block for maximum heat storage, but also to allow the radiator fan airflow to envelop and surround the engine block. Unlike conventional engines that require heat to be removed from the engine block, the present invention admits to reusing the engine coolant thermal energy to reheat the engine block. The engine coolant is pumped by a engine coolant pump through the heat exchanger and then through the engine block, through the engine radiator, to remove heat from the engine coolant and use the heat thus removed to reheat the engine block to keep it at an operating temperature close to the boiling point of the expansion fluid. Advantageously, a radiator fan may be driven by either the electric power from a battery or by means of the engine crank shaft to remove heat from the engine radiator by passing air through the engine radiator fins and directing said air back over the engine block to reheat the engine block to a temperature close to the boiling point of the expansion fluid. It is important that the fan speed and air CFM capacity be properly specified to just remove heat and not necessarily cool the engine block. Thus the radiator fan must be specified with a thermostat that activates the fan only when the engine coolant temperature is close to the boiling point of the expansion fluid. Thus minimal heat from the thermal battery is lost as wasted heat to atmosphere during the operation of the engine. A negative pressure will be generated inside the heat exchanger by the rapid condensation of the expanded fluid back to expansion fluid and caution must be exercised to make sure that the fluid circuits and the heat exchanger can handle a negative atmospheric pressure.

Advantageously, the recirculate expansion fluid could be directly sprayed inside of the exhaust tube to mingle and condense the flowing expanded fluid into its liquid form again. This ensures maximum use of the heat wasted from the exhausted expanded fluid from the engine. The condensed expansion fluid and the recirculate expansion fluid could then be returned through the heat exchanger for further cooling. The condensate and the expansion fluid thus obtained can then be recirculated as recirculate expansion fluid back to the expansion fluid storage tank.

Thus when the engine starter turns the drive shaft, the expansion fluid pump delivers a quantity of expansion fluid through the bypass valve flow regulator into the expansion chamber causing expansion fluid to expand into a vapor and become expanded fluid; and when the piston head is at top dead center of the cylinder chamber the intake cam shaft rotates such that a cam opens the intake valve and expanded fluid vapor is passed through the intake valve port into the cylinder expansion chamber to generate pressure and drive the piston head from top dead center to bottom dead center, and the piston head motion generates a force transmitted by the piston crank to turn the crankshaft and generate mechanical power using the thermodynamic potential of the expanded fluid vapor; and when the piston head is at bottom dead center the cylinder valve operating means closes intake valve closes and at the same time opens the exhaust valve to cause expanded fluid vapor to exit through exhaust valve port into the exhaust chamber for removal of exhaust expanded fluid as the piston head rises to top dead center again pushing expanded fluid vapor into the exhaust tube through a check valve and into the heat exchanger to mingle with recirculate expansion fluid and to cool and condense the expanded fluid vapor back into expansion fluid and to advantageously generate a negative vapor pressure to assist and pull the piston head back to top dead center to repeat the cycle. The check valve prevents backflow of condensate into the exhaust chamber to maintain a negative pressure and prevent condensate from entering the cylinder expansion chamber. The expansion fluid tank receives condensed expansion fluid from the heat exchanger above the level of the expansion fluid therein to prevent expansion fluid from flooding the heat exchanger. In the closed cycle format of the invention, an expansion fluid pump for pumping expansion fluid from the expansion fluid tank into bypass valve and flow regulator is provided. It is not necessary for the expansion fluid pump to be driven electric, however it is important that it can be controlled to completely shut down when required even if the engine is running. If the expansion fluid pump is connected to the crankshaft and powered by the crank shaft, an electric clutch must be used to disengage it when it is required to be turned off while the engine is in operation. The expansion fluid is then sent to the the expansion chamber to expand to expanded fluid repeat the process.

In a conventional engine format, the intake valves and the exhaust valves ride on cams which forces them to open and close against a cam spring compression force in a conventional fashion. However, it is important that the both the intake valve and the exhaust valve be sealked by positive pressure and not aspirate as in a conventional engine.

A flywheel is attached to the drive shaft connected to one end of the crankshaft preferably extends out of the crankcase through a shaft port to transmit the thermal engine power in the form of torque to any desired mechanical load such as the expansion fluid pump, and the engine coolant pump.

In the open cycle format of the present invention, the expansion fluid can be delivered into the expansion chamber by the expansion fluid pump, and by either gravitational potential or by pressurizing the expansion fluid tank. In the closed cycle format, no expansion fluid is lost and the same quantity of expansion fluid remains in the thermal engine cycle in vapor and liquid phase and is reused over and over again by means of condensation and expansion. In the case of an open cycle format the expanded fluid is exhausted into the atmosphere without the need for a heat exchanger.

In general operation of the closed cycle engine, heat is generated and stored in the thermal mass by one of several means. The first means is by passing electric current through resistive heating elements embedded in the thermal mass for a period of time and the second alternative means is by imposing an electromagnetic induction heating means on the thermal mass for a period of time, the third means is by exposing the thermal mass to infra red heat from infrared lamp radiators. A fourth means of heating can be used that involves radioactive heating materials such as thorium. If Thorium is used, a substantial radiation shield such as lead and carbon can be sued to shield the Thorium from outside exposure. Since the shield is also a thermal mass, a thick layer of shielding could be incorporated enough to reduce any possible radiation from contaminating the environment. Thorium is a chemical element with symbol Th and atomic number 90. Thorium was commonly used in gas mantles in the past. Thorium is used as an alloying element in non-consumable TIG welding electrodes, in high-end optics and scientific instrumentation. Thorium has a half-life of 7,340 years and melting point of 1750° C. and thus can be used as a heating source for the thermal mass up to 1200° C. for an indefinite period of time.

The thermal engine is started by the engine starter switch. Thus sends power to an electric engine starter and causes it to rotate the drive shaft connected to turn a crankshaft. If the expansion pump is directly driven by the crankshaft then the crankshaft turns the expansion fluid pump which pumps a quantity of expansion fluid from the expansion fluid tank through a flow regulator into the expansion chamber. However it is preferable that an electric expansion fluid pump be used so that it can be started and turned off by the engine starter switch. If the expansion fluid pump is driven by the engine crankshaft and since the speed of the engine can influence the speed of the expansion fluid pump, the engine power can exponentially decay if it slows down and then slows expansion fluid pump as well. Thus, preferably, the expansion fluid pump should be electric driven and made independent of the engine crankshaft motion. The bypass valve and the flow regulator allow only the prescribed amount of expansion fluid to pass into the expansion chamber and the rest is returned as recirculate expansion fluid through the exhaust tube to the expansion fluid tank by a recirculate tube. It is important to note that the recirculate expansion fluid need not pass through the exhaust tube but can go directly into the expansion fluid storage tank.

The heat stored in the thermal mass causes the expansion fluid to expand by a phase change into expanded fluid to generate pressure in the intake chamber. The turning of the crankshaft by the engine starter causes the piston head to move and when it rises to top dead center, the cylinder valve actuating means, which could be the intake cam shaft causes the intake valve to open while at the same time closes the exhaust valve. The pressurized expanded fluid in the intake chamber rushes through intake valve port into the cylinder expansion chamber and pushes the piston head to bottom dead center position turning the crankshaft and thereby rotating the exhaust cam shaft and the intake cam shaft to cause the cams to close the intake valve and also open the exhaust valve. When the intake valve closes the expanded fluid in the cylinder expansion chamber is exhausted by the piston head as it returns to top dead center position using the momentum stored in a flywheel. As the piston head returns to top dead center position, the expanded fluid exits the cylinder expansion chamber into the exhaust chamber through exhaust valve port. The expanded fluid is either transported through an exhaust tube to the heat exchanger in the closed cycle format of the invention, or it is expelled to atmosphere in the open cycle format of the invention from the exhaust tube.

In the closed format of the invention, the heat exchanger cools the expanded fluid vapor back into expansion fluid by using the engine coolant to cool the vapor. An exhaust check valve at the end of the exhaust tube causes a vacuum within the exhaust chamber as the expanded fluid condenses to expansion fluid. This vacuum is generated in the exhaust tube and transmitted to the cylinder expansion chamber and this increases the power of the thermal engine since when the exhaust valve port opens the negative pressure in the cylinder expansion chamber will, in addition to the energy stored in the flywheel, cause the piston head to rapidly return by negative pressure to top dead center position. This adds more power to the thermal engine since the invention essentially teaches the use of expansion fluid in both its pressurized vapor expanded fluid form and its vacuum condensate state to push and return the piston head from top dead center position to bottom dead center position and back to top dead center position. This vacuum assistance is possible in both the open cycle format and the closed cycle format if the exhausted expanded fluid is passed through a long enough exhaust tube before being exhausted to atmosphere. In such a case, the rapid cooling of the expanded fluid in the exhaust tube causes the expanded fluid to undergo a phase change from the vapor phase to the liquid phase and such rapid condensation results in a vacuum being generated momentarily in the exhaust chamber. Thus, by adjusting the length of the exhaust tube, it is possible to regulate the timing of the vacuum formed with the motion of the piston head as moves from top dead position center to bottom dead center position and then back to top dead center position.

At close to bottom dead center the turning of the crankshaft, the momentum stored in the flywheel, and the negative pressure of vapor condensation causes the piston head to rapidly move back towards top dead center to repeat the cycle and to a position that causes intake valve close while causing the exhaust valve to open. In a closed cycle format of the invention, the pressurized expanded fluid in the cylinder expansion chamber is pushed through the exhaust valve port into the exhaust chamber allowing the expanded fluid to exit the cylinder expansion chamber and through the exhaust tube and check valve into the heat exchanger. Alternatively the expanded fluid can exit the cylinder expansion chamber through the exhaust tube and check valve to bypass the heat exchanger and be expelled directly to atmosphere. The piston head freely returns to top dead center by the continued angular momentum from the rotation of the crankshaft and flywheel allowing the remaining elements of the expanded fluid out of the cylinder expansion chamber into the exhaust chamber and then to cool either in the exhaust tube or in the heat exchanger to and generate a negative pressure of vapor condensation so that the cycle can continuously repeat until stopped. To stop the cycle, the bypass valve simply bypasses expansion fluid through to the recirculate expansion fluid and closed off the flow to the flow regulator and stop the flow of expansion fluid into the thermal battery.

The thermal mass can be constructed with multiple layers of metal slabs so that it is easier to handle and easier to conform to the space requirements of a vehicle. In one preferred embodiment, the thermal mass is constructed from layers of metal slabs which form a stack with passages and openings that are needed for the embedded heating means and to allow heat transfer fluid to freely and evenly flow through the entire surfaces of the thermal mass to effectuate adequate heat transfer to the heat transfer fluid.

The thermal mass can be made from a single casting with all the required passages already configured within it for the heat transfer fluid and the heating means. Thermal insulation surrounds the thermal battery vacuum case to insulate and prevent loss of heat energy to the environment. Preferably, the thermal insulation is made from such as polyamides and ceramics fiber materials that can withstand extremely high temperatures. Such materials are available as wrap around tapes from companies such as Engineered Tapes Inc., and ABS Thermal Technologies in New York. The thermal mass is preferably made from stainless steel and metal alloys, but can also be made from ceramics, silicates, clays or carbon compounds. Preferably a dense material with a high heat storage capacity should be used to achieve a high storage heat capacity in the thermal mass. The heat energy, q, stored in a material of mass m, is proportional to the temperature difference, dt, it undergoes and its specific heat capacity c_(p) as given by the formula:

q=mc _(p) dt

Such dense materials that may be used for a thermal mass include iron, lead, stainless steel, titanium, aluminum, molten salts, carbon composites, fiber glass composites and ceramics. The heat energy storage density is a function of the density of the material since the mass is a function of the density. Examples of the heat storage density of some materials are shown in the table below:

Heat storage density Operating temperature Material kJ/m²° C. range, ° C. Aluminum 2484  680 Cast Iron, 3889 1151 Stainless Steel, Ceramics 2800 2000 Taconite 2500 2000 Saltstream ™ 565 1960  565

The expansion fluid tank should be made from durable water and pressure resistant materials such as Aluminum, Stainless steel or Fiberglass including Carbon. Since the expansion fluid tank can be pressurized in some instances, it must be designed to hold adequate pressure and its construction should follow adequate guidelines for manufacture of pressure tanks of the required pressure ratings.

The engine block and engine components can be constructed from metal alloys commonly used in the manufacture of standard combustion engines. However since the thermal loads that the thermal engine is subjected to can be far less that regular combustion engines, it is possible to construct the engine components from aluminum alloys, ceramics, plastics and even carbon fiber materials. If water is used as an expansion fluid, it is even possible to manufacture the engine and its components using high temperature engineering plastics such as mentioned earlier. The design of the cylinders in the cylinder head could be augmented by inserting stainless steel sleeve cylinders to prevent the wear of the plastic due to the friction of the piston head sliding on the cylinder walls.

Advantageously, the use of engineering plastics could make the thermal engine as light as possible to compensate for the additional weight that is needed for the thermal battery. Some other components of the thermal engine such as the cams and the camshaft could also be made from adequate engineered plastics that can withstand mechanical loads and heat. In all the cost of manufacture of the thermal engine can be reduced considerably by a suitable choice of materials.

The engine starter is mechanically coupled to the drive shaft by either a gear or a pulley and belt. The engine starter is preferably an electric starter of conventional design that is operated by an electric battery. It could also be an air pressure starter or a rope starter similar to conventional pull rope starters used for small combustion engines. In the case when there are multiple piston heads and cooperating cylinders incorporated into the thermal engine, the power stroke of at least one piston head is opposed to the exhaust vacuum stroke of another piston head. In this case, the thermal engine will start when expansion fluid is simply delivered to the expansion chamber by opening the flow regulator and turning on the engine starter. Thus the thermal engine may be started by simply opening the flow regulator and allowing expansion fluid to push the piston head in a power stroke to bottom dead center and allowing at least another piston head to come to top dead center to the restart the cycle.

The engine is a two-stroke engine and unlike a four-stroke engine, the thermal engine can be started by a compressed air acting as the engine starter. In the case of a small engine when the thermal engine could simply be rotated by applying mechanical torque on the drive shaft, the engine starter could simply be a crank that can be manually placed on the drive shaft to turn the drive shaft and start the thermal engine.

The starting of the thermal engine power cycle causes the expansion fluid pump to deliver a quantity of expansion fluid through the bypass valve and the flow regulator into the expansion chamber and the heat stored in the thermal mass causes the expansion fluid to become heated and to undergo a phase change and become an expanded fluid vapor within the expansion chamber. The expanded fluid is under vapor pressure and expands in the expansion chamber from where it is transmitted through intake tube under pressure into the intake chamber. The valve cover forms the two fluidly separate chambers that form the intake chamber alongside the exhaust chamber where it abuts the valve block. Every intake valve port is in common fluid communication with the intake chamber and so any intake valve that is open will immediately transmit the pressure of the expanded fluid into the cylinder expansion chamber to push its corresponding piston head from a position substantially at top dead center to bottom dead center, thereby rotating the crankshaft and producing mechanical energy. When the piston head is at bottom dead center and about to rise again to top dead center, the cam causes the intake valve to close and simultaneously causes the exhaust valve to open and to allow the piston head to freely return to top dead center and since every exhaust valve port is in common fluid communication with the exhaust chamber any exhaust valve that is open will immediately transmit the expanded fluid from the cylinder expansion chamber into the exhaust chamber and allow the continued angular momentum and rotation of the crank shaft and flywheel so that the cycle can continuously repeat.

Advantageously, the exhaust chamber is fluidly connected by the exhaust tube to the input of a heat exchanger so that expanded fluid may be condensed therein to generate a negative pressure in the exhaust chamber to generate an additional vacuum force to pull on the piston head as it returns to top dead center position. This additional vacuum force can contribute a substantial torque to the thermal engine during operation. The fluid path of the expanded fluid in the heat exchanger outputs to the suction of the expansion fluid pump and then back into the expansion fluid tank so that the expansion fluid tank may be subjected to a buildup of a slight vacuum over time. A expansion fluid tank check valve above the expanded fluid level is placed on the expansion fluid tank to prevent any vacuum loss from the expansion fluid tank, but can allow any excess pressure from exhausted expanded fluid to exit the expansion fluid tank. During the exhaust stroke, if there is insufficient heat removal capacity from the heat exchanger, expanded fluid in vapor form may exit the heat exchanger and fill the headspace in the expansion fluid tank but any excess pressure is removed by the tank check valve to prevent backpressure buildup in the exhaust chamber. However, since the exhaust valve is closed at top dead center as soon as the exhaust stroke is completed the vacuum starts to build up again in the heat exchanger and the expansion fluid tank, vapor from prior power strokes has evacuated all the head space of the expansion fluid tank and the vacuum build up in the expansion fluid tank, the heat exchanger and the exhaust chamber and the vacuum thus formed will be used to assist the next exhaust cycle.

Further, a cooling fan may be optionally attached to output shaft to cool the engine coolant in the radiator. The thermal engine includes a heating means including at least an infrared heater, and alternatively, a resistance heating element extending into the thermal mass and a resistance heating element circuit; a power connector for delivering electric current through the at least one heating means and thereby heating the thermal mass. Alternatively, the thermal mass heating means includes an electromagnetic induction heating means to heat the thermal mass by inductive heating; said electromagnetic induction heating means either may be incorporated as part of the thermal mass or may be a separate unit from the thermal mass so that the thermal mass may be heated quickly and non-intrusively by an external electric power source. The thermal mass optionally includes part of the engine block, and optionally the entire chassis of the vehicle or device using the engine. The external electromagnetic induction heating means may be an induction coil proximally placed to heat the thermal mass without any contact with the thermal mass, so that in the event that the thermal engine is installed in a vehicle or mobile device, the thermal mass can be heated quickly by just passing through the vehicle or mobile device through the electromagnetic field of such the electromagnetic induction heating means without contact. To take advantage of as large a thermal mass as possible the thermal mass may additionally include the material the engine made from so that if insulated, the thermal loss can be minimal. The Infrared heating bulbs can be used to directly heat the thermal mass by radiation. Such heaters are readily available from companies like Dykast Inc. Watlow 1/32 Din digital Temperature controller can be used to control the temperature of the thermal and preferably Avatar 60 Amp SCR for switching 10 kW load with 2 second soft start and voltage limitation controllers can be used to control the thermal heating means such as the infrared heaters. It is important that an electric rotary disconnect be incorporated into the thermal controller design to cut off power from the main supply. Thermocouple cable with Harting (or similar) quick connect Female plug can be used for durability and thermal protection of the thermocouple since a lot of heat will be generated during the charging of the thermal battery.

It is important that the intake chamber be insulated as much as possible so that the expanded fluid vapor retains as much heat as possible before it is introduced into the cylinder expansion chamber. It is important that the exhaust chamber not be insulated so that as much heat can be taken out of the expanded fluid vapor to reduce it to expansion fluid liquid after it has done its work.

The thermal engine preferably operates on a noncombustible expansion fluid such as water or a refrigerant fluid; it is important that the expansion fluid have as high a heat of vaporization as possible.

Water and refrigerants such as ammonia have the highest heat of vaporization per kilogram. Some examples of heat of vaporization are given below:

Heat of vaporization Heat of vaporization Compound (kJ mol⁻¹) (kJ kg⁻¹) Methane 8.19 760 Ethanol 38.6 841 Methanol 35.3 1104 Ammonia 23.35 1371 Water 40.65 2257

The thermal engine additionally includes an expansion fluid tank in fluid communication with the expansion chamber.

It is important that the thermal energy that causes expansion fluid to expand to expand fluid not be directly transferred directly by contact with the thermal mass since this can cause elevated uncontrolled pressure. However it is quite possible to use the thermal mass to directly heat the expansion fluid by controlling the amount of expanded fluid one exposes to the thermal mass. However uneven heating and expansion fluid distribution across the thermal mass can cause localized cooling of the thermal mass and a reduction in efficiency and power. Also superheating of the expansion fluid can occur in which case a lot of energy will be wasted and never recovered. Thus it is advantageous to use a suitable heat transfer fluid such as helium, nitrogen or air to effectuate the even transfer of heat energy from the thermal mass to the expansion fluid.

The expansion fluid pump supplies expansion fluid from the expansion tank to the expansion chamber so that when the expansion fluid enters the expansion chamber it absorbs heat from the heat transfer fluid and it expands quickly and pressurizes the expansion chamber with uniform vapor pressure. This way the vapor pressure is constantly transmitted from the expansion chamber to intake valve to feed all the cylinders as needed. Thus as each intake valve opens, the pressure is readily available to power the piston head and run the engine. Thus unlike conventional engines, the intake chamber is always under pressure and all the intake valves are subjected to this pressure so that when each opens it is fed pressurized expanded fluid from the intake chamber. In this way, there is very little fluid regulation needed to ensure adequate operation of the thermal engine.

In yet another embodiment of the invention, the expansion fluid is an electrolyte such as water. The expansion fluid could contain dilute acids or salts to increase the efficiency of the electrolysis. An expansion fluid pump pumps a pressurized quantity of expansion fluid from an expansion fluid tank through an excess bypass control valve and then through a flow regulator. The bypass control valve allows a predetermine amount of the expansion fluid to flow through the flow regulator into the expansion fluid passageways of the thermal mass while bypassing excess expansion fluid as recirculate expansion fluid through the second heat exchanger path and then back to an expansion fluid storage tank. The flow regulator allows only the prescribed amount of expansion fluid to pass through an electrolysis chamber before it enters the thermal mass passageways. An electric current is used to generate Oxyhydrogen, a mixture of hydrogen (H₂) and oxygen (O₂) gases within the electrolyzer therein. While it is known that Oxyhydrogen gas can explode to form steam when at the stoichiometric ratio of its components oxygen and hydrogen, it can also implode to form water. However, no prior art describes how to cause the Oxyhydrogen gas to remain as auto-ignited steam for use as a power generator. A lot of literature has been published on the phenomena of heat and explosion generation from Oxyhydrogen gas. However, the present inventor has investigated the claims made for the use of Oxyhydrogen gas as an over unity power generation means and found them to be false. The amount of energy used remains constant with the amount of energy it generates. However if one considers that a given volume of the gas can be reduced to about

$\frac{1}{1400}$

times its original volume, then one can generate either pressure or a vacuum using the gas. In theory, Oxyhydrogen, is a gas and not steam. Since steam expands to about 1400 times its volume as water, Oxyhydrogen gas will expand when there is no thermal energy loss and when it is ignited by the heat of reaction δE that goes to form steam from water molecules. All its thermal energy comes from ignition reaction

H₂+2O₂→2H₂O+δE

Thus the formation of a dry gas form of Oxyhydrogen formed within a fluid matrix generates a gas as opposed to steam. If this gas is then subjected to high temperatures from a spark or from a thermal mass it will ignite and form steam instead of water. Thus it can explode to 1400 times its volume when subjected to temperatures greater than its phase change temperature. That is why a spark or a flame which is above the phase change temperature can ignite the gas and cause it to explode. It is a very efficient way to use any energy source above the phase change temperature to convert expansion fluid to expanded fluid. However it accords no magic or over unity energy.

In the presence of a heat absorber however, the heat removed from the Oxyhydrogen when ignited can immediately recondense any local steam thus formed by the reaction resulting in an implosion to water. Thus it is important that the Oxyhydrogen gas thus generated by electrolysis of the expansion fluid be contained as bubbles within the flowing expanded fluid that enters into the thermal battery and that the heat caused by the reaction not be removed from. An electrolytic cell uses electricity from a battery to split the expansion fluid (water in this case) into hydrogen and oxygen. When molecules of this gas are ignited by either a heat source of a spark above the phase temperature of the expansion fluid, they form steam since the reaction has no time to condense the steam and the heat SE thus generated can cause the water thus formed to explode to 1800 times its volume as steam. Heat generated by this explosion within the thermal passageways adds to the heat from thermal mass by means of an electric power source. No additional energy is gained when one considers that the source of the heat is from a battery. However it is a means of very efficiently and continuously converting an electric energy source to thermal energy in the thermal engine. It is thus important that the Oxyhydrogen gas be subjected to temperatures much higher than 500° F. to autoignite and explode and remain as steam.

The Oxyhydrogen thus generated must be encapsulated as bubbles within the expansion fluid and when in contact with the thermal mass and will auto ignite and generate additional pressure as it converts to expanded fluid within the hot thermal battery. In this form of the invention, the electrolysis can be performed within the flow stream of expansion fluid that is channeled into the thermal mass to gain heat from an electric current without introducing any additional heating elements except for a battery. It is like direct heating of the expansion fluid using an electric current.

In this form of the invention, the electrolysis can be performed by a series of metallic anodes and cathodes that are sealingly within the flow stream of expansion fluid that is channeled into the thermal battery expansion passageways.

In yet a very innovative and inventive manner, the Oxyhydrogen gas can be generated by electrolysis in a cooler than temperature than the phase change temperature of the expansion fluid. This can be done within the recirculate expansion fluid and then removed therefrom and directed into the first heat exchanger passageways where the expanded fluid is being cooled to expansion fluid below the phase change temperature. In this case the Oxyhydrogen gas will immediately implode to about

$\frac{1}{1800}$

times its original volume. The implosion is a result of the gas thus formed reducing in volume back to a fluid phase from a gas phase. However, it is important that the electrolysis be done at an electrode temperature higher than the phase change temperature of the expansion fluid. My investigation shows that when the current to the electrodes exceeds the electrolytic capacity of the electrodes, the local extra energy from the electrodes cause the phase change temperature of the Oxyhydrogen and it is immediately form as steam (already expanded gas). Thus when this steam is cooled at the heat exchanger, one can generate a tremendous vacuum within the exhaust tube that acts within the exhaust chamber. Thus one can effectuate the exhaust stroke and cause a negative vacuum pressure to occur while the piston is rising from Bottom dead center to increase the power of the engine. Thus the electrolysis of water, or any electrolyte can be used to power the engine both in a positive pressure form at the intake and as a negative pressure form at the exhaust.

In accordance with the present invention, a thermally charged thermal battery is used to generate mechanical energy by a phase change of a liquid such as water. The thermal energy causes the expansion fluid to expand into a gas by a phase change and thus permits the thermal engine to run like a conventional engine without much change to the engine configuration.

An object of the prevent invention is to provide a thermal engine which can be operated with an expansion fluid having the most suitable thermodynamic properties to achieve a high degree of efficiency during operation. An engine of this kind, in accordance with the invention, can be optimized by its geometry through maximizing the thermal mass and minimizing the surface area of the thermal battery for storing a maximum amount of thermal energy in the form of a direct heat.

Essentially, a heat storing thermal battery is incorporated into the engine which permits energy to be stored thermally instead of chemically as in the case of a conventional electric battery. Advantageously, the entire engine block can be used as a thermal source in the form of a thermal mass, so that a large amount of thermal energy can be stored for later use. The thermal battery can be charged with heat to a high temperature using electric heaters, electromagnetic induction heaters or other forms of heat generators incorporated into of the thermal battery. For example a solar powered heat generator such as a lens can be used to focus heat on the thermal battery during charging to reduce the cost of using conventional electric energy sources. In the case when a fluid can undergo a phase change with very little heat, it is possible to use very low temperature thermal heating means to store energy in a thermal battery. It is possible that with the advances in nuclear technology that a miniscule and well-protected thermonuclear heating means could be incorporated into a well-protected radiation shielded thermal battery. In case of emergencies, it is possible to use a chemically based heating fuel to generate heat that can be stored in the thermal battery.

Moreover, the exhaust from the thermally expanded fluid from the thermal engine can be cooled to generate a reverse condensation liquid phase vacuum that could assist in the return cycle by pulling on the piston head when it is at top bottom center. In such a case, the maximum potential of the expansion fluid during condensation and creating a vacuum could be used in conjunction with its expansive energy. An expansion fluid such as water can be injected into the thermal mass of the thermal engine to generate steam and power the thermal engine. Optionally, a combination of water and ethanol and other fluids may be used as an expansion fluid. Advantageously, much more energy can be stored in such a thermal battery than in a conventional electric battery of the same weight. This can be demonstrated by simply exhausting the electrical energy of an electric battery of a given mass to heat up a thermal mass of the same mass.

It is important note that there exist other types of electrical thermal batteries which use liquid lithium and other salts as electrolytes. These existing electrical batteries are only suitable for storing electrical energy. The present invention is a true thermal battery which can be used to supply heat and electrical energy stored in the form of heat and electrolyte simultaneously. Advantageously, the present thermal battery can be used in conjunction with a molten electrolyte contained within the battery as a thermal mass to store both heat potential energy and electric potential energy simultaneously. Without limiting the scope of the invention, however, the preferred mode of operation is in a pure thermal mode wherein the thermal battery is simply a thermal mass.

A liquid such as water can be used as an expansion fluid, and part of the thermal mass can be projected into the cylinder to create an additional thermal storage source for generating efficient vapor phase change. If the entire engine block is used as a thermal mass, additional thermal energy can be stored by proper design and insulation of the entire thermal engine. Additionally, the expansion fluid itself can store thermal energy by heating it to a temperature just below its phase change point. By pressuring the expansion fuel tank the boiling temperature of the expansion fluid could be substantially increased so that it can be heated to a temperature higher than its regular boiling point before it is exposed to the thermal mass. The expansion fluid in the expansion fluid tank may be heated by tank electric heaters so that during charging, the expansion fluid may also be pre-charged with thermal energy to near its boiling point to increase its thermal potential.

The supply of the expansion fluid quantities can be controlled by means of electronics controlling the expansion fluid pump so that an exact metering of the expansion fluid can be achieved which has at least a level of control for the different thermodynamic properties of different expansion fluids.

The thermal battery case is preferably made from materials that have a high thermal resistance and melt temperature. Ceramics could be used to ensure that the thermal mass can be taken to the highest possible temperatures without melting the thermal battery case. The thermal battery could be either separate or incorporated into the design of the engine block. In the case when it is incorporated directly into the engine block the thermal battery case could be incorporated as part of the design of the engine block with the thermal mass expansion chamber directly incorporated as part of the engine block.

The thermal battery vacuum chamber must be designed to maximally surround the thermal mass so that no heat can be transmitted by conduction or convection from the thermal mass to the thermal battery case by conduction or convection. Where possible, the conductive portions where the thermal mass contacts the thermal battery case should be minimized so that the thermal mass is essentially suspended inside the thermal battery vacuum chamber by minimally conductive members. A vacuum resistant material should be used to construct the thermal battery case to prevent the loss of vacuum, thus preferably the thermal battery casing could be made from glass or from a metal alloy of suitable properties. The outer thermal insulation of the thermal battery case should be designed for minimal radiation. Preferably, the interior wall of the thermal battery vacuum chamber should be reflective to heat so that radiation is stored inside of it by reflection with minimal losses. The thermal battery case could be made from thermally insulating materials so that as much heat is stored within the thermal battery as possible. The thermal battery vacuum chamber should be evacuated to a high degree to avoid heat loss during operation. All fluid delivery passages and tubes should be insulated to a very high degree to prevent heat loss and their lengths should be minimized as much as possible.

Since there is no need to compress a fluid for firing and combustion, all the engines should be designed as two stroke engines, with a single stroke for a power stroke and a single return stroke for an exhaust stroke. The in the preferred embodiment, pressurized expanded fluid enters the intake chamber and serves all the cylinder expansion chambers simultaneously. This reduces the complexity of the expanded fluid control system since the expanded fluid inside the intake chamber is always pressurized during operation and ready to feed pressurized expanded fluid into each cylinder expansion chamber when its intake valve opens. Each intake valve opens when its piston head is at its top dead center and again closes when its piston head is at bottom dead center. Each exhaust valve opens when its piston head is at its bottom dead center and again closes when its piston head is at top dead center. The exact position when the valves open could be adjusted to compensate for lag in the delivery rate of the expanded fluid and the exhausted rate of the expanded fluid. In some cases, it is possible to isolate each cylinder to have its own intake chamber and its own exhaust chamber. In this case, it is possible to rearrange the power strokes of each piston head so that they can be sequenced as necessary to maximize the power outtake of the thermal engine.

A flywheel is essential to keep the cycle going since very little power is generated during the motion of the piston head from bottom dead center to top dead center even though if a vacuum is maintained in the exhaust chamber a substance force could be generated to assist the return of the piston head. In the case when a closed cycle thermal engine is built the exhausted expanded fluid vapor should be cooled in a non-resistive heat exchanger. The passageways for the expanded fluid vapor in the heat exchanger should be free from any back pressure and the heat exchanger should be able to quickly remove all the heat of condensation from the expanded fluid so that it can quickly condense to expansion fluid and thus recycled as quickly as possible before losing most of its heat. In fact the heat removed by engine coolant passing through the heat exchanger should be equal or more than the heat of condensation of the expanded fluid so that the liquid phase of the expansion fluid remains as close to its boiling point as possible. This ensures that very little heat is taken from the thermal mass by the expansion fluid to re-expand it to a vapor phase. The expansion fluid tank could also be incorporated as part of the heat exchanger. This way the expansion fluid is stored in the heat exchanger as opposed to using a separate expansion fluid tank for the same purpose. The condensate expansion fluid from the heat exchanger can be held in a segment of heat exchanger, which will act as an expansion fluid tank to minimize the size and complexity of the thermal engine, and more importantly to minimize the exposure of the condensed expansion fluid to the atmosphere. The expansion fluid from the expansion fluid tank can then be transferred directly by the expansion fluid pump to the expansion chamber for immediate reuse as needed. If the heat exchanger is large enough, the condensate could be taken directly from the heat exchanger output and reused as the expansion fluid so that it can act directly as the expansion fluid tank itself.

In the case when an open cycle thermal engine is built the exhausted expanded fluid vapor could be exhausted directly to the atmosphere and not reused. The most suitable expansion fluid for this purpose is water since it is environmentally friendly. In the open cycle format of the invention, the thermal engine is provided with an expansion fluid tank that can store an adequate amount of expansion fluid for the required period of use of the thermal engine. Then, the exhausted expanded fluid could be passed through the heat exchanger or simply expelled to atmosphere as vapor. Preferably, the heat exchanger can be a plate heat exchanger with alternating passages for the engine coolant and the expanded fluid and recirculate expansion fluid. It could also be simple coiled tube-in-tube heat exchanger that could be incorporated with a check valve at its end that only allows fluids to pass to atmospheric pressure so that as the expanded fluid is exhausted it cools inside the exhaust tube and condenses to a liquid phase to form a vacuum in the exhaust tube and the exhaust chamber and the check valve closes to maintain the vacuum. The vacuum subjects the exhaust valve to a negative pressure that can be used to assist the piston head to rise to top dead center when the said exhaust valve is opened. When the vacuum subsides during the power cycle, the check valve relaxes and opens and expansion fluid is expelled into the atmosphere. This way, only liquid is exhausted as a wasted fluid from the engine. No heat exchanger may be needed if there is an adequate supply of expansion fluid, but reusing the expansion fluid can assist in reducing the energy drawn from the thermal mass. In such a case, the condensed expansion fluid can be recaptured in the expansion fluid tank under atmospheric conditions. In the open cycle embodiment of the present invention, the expansion fluid tank should be in fluid communication with the atmosphere so that no back pressure is generated by the exhausting expanded fluid, and if the heat exchanger becomes too hot, the expanded fluid vapor can simply escape from expansion fluid tank to atmosphere without generating a back pressure on the intake chamber. In yet another embodiment of the open cycle, the heat exchanger could be submerged inside the expansion fluid in the expansion fluid tank to exchange heat directly with the expansion fluid stored therein. This allows a lot of the exhaust heat to be captured. However if this is done it is important that the output of the heat exchanger exhaust be above the liquid level so that in the case of a vacuum being generated by the condensate, the expansion fluid will not be sucked backwards into the exhaust chamber.

While the invention can be used only with a noncombustible phase change liquid such as water it may also be used in combination with or separately with a potentially combustible expansion fluid that have a high expansion value.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other objects, advantages, and features of the invention will become apparent to those skilled in the art from the following discussion taken in conjunction with the following drawings, in which:

FIG. 1 is a perspective bottom view of motor vehicle showing incorporation of the elements of the preferred embodiment of the present system into the undercarriage and engine compartment.

FIG. 2 is a perspective upper view of the embodiment of FIG. 1 seated in a motor vehicle frame.

FIG. 3 is a separate, perspective view of the preferred thermal battery, broken away from the rest of the system.

FIG. 4 is a partially exploded perspective view of the thermal battery of FIG. 3.

FIG. 5 is a perspective side view of the present thermal battery with a corner broken away, revealing the vacuum chamber and thermal chamber.

FIG. 6 is a plan side view in partial cross-section of the present system showing part of the thermal engine broken away.

FIG. 7 is a perspective top view of the system.

FIG. 8 is a perspective top view of the system as in FIG. 7 but from the opposite side, illustrating the electrolytic cell and battery in exploded relation.

FIG. 9 is a close-up, cross-sectional side view of the electrolytic cell and battery of FIG. 8.

FIG. 10 is a first schematic view of the system illustrating heat flow.

FIG. 11 is a second schematic view of the system.

FIG. 12 is an illustration of thorium within a radioactive shield, which is optionally included in the system for heating the thermal mass.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.

Reference is now made to the drawings, wherein like characteristics and features of the present invention shown in the various FIGURES are designated by the same reference numerals.

First Preferred Embodiment

The present invention relates generally to the field of engines that convert heat into mechanical energy. Referring to FIGS. 1-12, a thermal engine 100 is disclosed which may be used to power a vehicle 300 such as a car or a Train. Thermal engine 100 uses the thermodynamic properties of an expansion fluid 107 and the pressure it generates during phase change to expanded fluid 145 to convert thermal energy to mechanical energy.

In its most basic form, as mentioned above generally, the thermal engine 100 incorporates several conventional engine elements including valve cover 111 sealingly mated to valve block 112 sealingly mated to engine block 113 and with a crankcase 114 sealingly mated to sump 115. These components of the thermal engine 100 could be injection molded from suitable engineering plastics and ceramic composites and appropriately lined with durable inserts in areas where wear might be a problem.

The engine block 113 has one or more longitudinal spaced cylinder chambers 140 that are bored through it with axes perpendicular to its open face within each of which a piston head 103 is slidably and sealingly retained to form a variable volume cylinder expansion chamber 108 between a piston head 103 and a valve block 112. The other end of the engine block 113 is sealingly connected to a crankcase 114. The anticipated operating temperature of the engine block 113, the valve cover 111, the valve block 112, the crankcase 114, the sump 115 and the piston head 103 is below the melt critical operating temperatures of some engineering plastics and inexpensive metals so these components could be constructed from durable materials such as aluminum allows, plastics such as Peek, Vespel® SP-1 Polyimide, Melding 7001 Polyimide, Kapton® Polyimide, Kaptrex® Polyimide, Torlon® 4203, Vestakeep® PEEK, Ceramapeek®, Ryton®—PPS—40% Glass-Filled and Celazole® PBI. Celazole® PBI offers the highest heat resistance and mechanical property retention over 400° F. well above the boiling point of most liquid refrigerants.

The cylinder chamber 140 and the piston head 103 can be made from aluminum or can be coated with a rust deterring coating and alternatively can me made from stainless steel sleeves to prevent wear due to the sliding motion required of piston head 103. The piston head 103 has piston rings 103R that form an adequate slide seal with the cylinder chamber 140. A crankshaft 110 is mechanically linked to the piston head 103 opposite the valve block 112 by a piston crank 104. The valve block 112 has intake valve ports 117 with intake valves 118 and the same number of exhaust valve ports 119 with exhaust valves 120 for sealing and fluid communication with the cylinder chamber 140 in the engine block 113; the valve cover 111 sealing forms an intake chamber 121 and an exhaust chamber 122 over the intake valve ports 117 and the exhaust valve ports 119 respectively.

For the purposes of the invention, the intake chamber 121 is sealingly and fluidly connected to receive expanded fluid 123 from expansion chamber 136 through an intake tube 124; the exhaust chamber 122 is sealingly and fluidly connected to an exhaust tube 125 at the end of which is serially connected a check valve 126 for stopping expansion fluid to renter the exhaust chamber; a vapor trap 128 is placed before the check valve 126 at the end of the exhaust tube 125; check valve 126 sealingly and fluidly connects to a radiator 130 which fluidly connects to a first heat exchanger path 143 for circulating expanded fluid 123; and a second heat exchanger path 144 for circulating expansion fluid if it is used for cooling expanded fluid, or alternatively for connecting said second heat exchange path to an air blower to cool expanded fluid 123.

Check valve 126 sealingly and fluidly connects to first heat exchanger path input 143 i to receive expanded fluid from the radiator 130; in one embodiment first heat exchanger path input 143 i sealingly also sealingly connects to electrolytic cell gas output 181 of an electrolytic cell 175 with battery 179. Electrolytic cell 175 is configured with a Cathode 176 and an Anode 177 for generating Oxyhydrogen when water is used as an expansion fluid 123, otherwise it is unnecessary. The expansion fluid tank input 145 o sealingly and fluidly connects to expansion fluid pump suction 138 i; expansion fluid pump output 138 o sealingly and fluidly connects to the bypass valve 154; and finally, bypass valve 154 bypass valve 154 has two outputs which sealingly and fluidly connects to recirculate tube 155 and to flow regulator 159 respectively. Flow regulator is connected to the input of an electrolytic cell 175 and the output of the electrolytic cell 175 connects sealingly to pressure chamber 152 so that expansion fluid can pass through the electrolytic cell and into the pressure chamber 152.

Bypass valve 154 is designed to regulate the pressure and amount of flow of expansion fluid 123 into pressure chamber 152 and to provide for even pressure distribution of expansion fluid 107 the recirculate tube 155 and the flow regulator 159. Thus by regulating the flow regulator 159, the amount of recirculating expansion fluid 156 and the flow of expansion tube to both the electrolytic cell 175 and the pressure chamber 152 can be controlled. Bypass flow valve 154 allows excess expansion fluid 107 to be returned through the recirculate tube 155 to expansion fluid tank 145.

The electrolytic cell is connected via a positive and a negative lead to a 12V or 24V battery that is used to power engine starting means 139. In the case of using electrolytic gas 182 to generate pressure and thermal energy in the pressure chamber 152, the electrolytic gas 182 generated by the electrolytic cell 175 when turned on in the presence of expansion fluid can just be allowed to flow into the pressure chamber 152 and explode therein. As expanded fluid 123 is generated therein. In the case when a vacuum assist is required, the electrolytic gas 182 can be gathered as a buoyant gas in the electrolytic cell 175 be directed through an electric gas supply tube 178 which connects the electrolytic gas output 181 of the electrolytic cell 175 a first heat exchanger path input 143 i to provide electrolytic gas 182 inside the first heat exchange path 143. This allows the electrolytic gas to implode and create a vacuum therein which is then transmitted to the exhaust chamber 122 to vacuum assist and increase the power of the thermal engine 100.

The recirculate tube 155 is connected to the second heat exchange path input 144 i before it enters expansion fluid tank 145 to allow the recirculate expansion fluid to exchange heat with the expanded fluid 123 from radiator 171. This allows the heat from the expanded fluid 123 to be absorbed back into the recirculating expansion fluid 107 before it returns to expansion fluid tank 145. By controlling flow regulator 159, the amount of fluid fed into pressure chamber 152 can be regulated to regulate the power of thermal engine 100. Finally the output of pressure chamber 152 fluidly and sealingly connects sealingly to intake tube 124 to transport expanded fluid 123 to intake chamber 121.

The first heat exchanger path input 143 i of heat exchanger 127 is connected to the output of radiator 130 to receive expanded fluid 123. The recirculate expansion fluid 156 is connected to a second heat exchanger path input 144 to pass through second heat exchanger path 144 and to thermodynamically interact and exchange heat with expanded fluid 123 passing through the first heat exchanger path 143. Both the output from first heat exchanger path output 143 o and the second heat exchanger path output 144 o return expansion fluid and condensed expanded fluid respectively back to expansion fluid tank 145 to be reused.

A thermal battery 105 consisting of a contiguous thermal battery vacuum chamber 131 within which is contained a sealed thermal mass chamber 132 for containing a thermal mass 106. Thermal mass chamber 132 encloses thermal mass 106 and the volumetric space between thermal mass 106 and thermal mass chamber 132 forms heat transfer fluid chamber 133. Thermal mass chamber 132 surrounds thermal mass 106 and the thermal battery vacuum chamber 131 surrounds the thermal mass chamber 132 so that a vacuum can be pulled in the thermal battery vacuum chamber 131 to surround the thermal mass chamber 132 and insulate it from convective heat loss. Thermal mass 106 can be made from stainless steel interspersed with aluminum. Aluminum melts at temperatures of about 1,221° F. (660.3° C.) and so it acts to store phase change heat within the thermal mass 106 at temperatures above 1233° F.

Sealed heat transfer fluid tubes 137 sealingly and fluidly connect the heat transfer fluid chamber 133 to a heat transfer fluid pump 134 to circulate heat transfer fluid 135 such as air, steam, helium or nitrogen through heat transfer fluid chamber 133 for uniform heat removal from thermal mass 106, and for transporting said heat transfer fluid 135 to a pressure chamber 152 that may be located a distance from the thermal battery 105. Pressure chamber 152 may also be located within the thermal battery 105. The heat transfer fluid tubes 137 sealingly pass through the walls of the thermal battery vacuum chamber 131 and sealingly connect to the heat transfer fluid chamber 133 to continuously circulate heat transfer fluid 135 between the pressure chamber 152 and through and the heat transfer fluid chamber 133 without introducing any heat transfer fluid 135 into the thermal battery vacuum chamber 131. Thus the integrity of the vacuum within the thermal battery vacuum chamber that surrounds the thermal mass chamber 132 is maintained. The thermal battery vacuum chamber 131, the thermal mass 106, the thermal mass chamber 132, the heat transfer fluid tubes 137 and the pressure chamber 152 must all be constructed from durable high melting point materials that do not rust such as stainless steel, titanium or ceramics. The thermal battery vacuum chamber 131 must be made from heat resistant and low expansion materials such as ceramics and metal allows. It cannot be made from plastic or aluminum since it must withstand very high temperatures.

The heat transfer fluid tubes 137 are preferably tubes of suitable diameter for easy flowing of the heat transfer fluid 135 by means the heat transfer fluid pump 134 and can be welded through the walls of the thermal battery vacuum chamber 131 and then through the walls of thermal mass chamber 132 to sealing and fluidly communicate with the and the heat transfer fluid chamber 133. Advantageously, the pressure chamber 152 can be located a distance away from the thermal battery 105 itself and still effectuate the expansion of expansion fluid 107 to expanded fluid 123 by means of a phase change using heat transferred by the heat transfer fluid 135 from the thermal mass 106.

The pressure chamber 152 receives expansion fluid 107 from bypass flow valve 154 and excess expansion fluid 107 is returned through the recirculate tube 155 to expansion fluid tank 145. By controlling flow regulator 159, the amount of expansion fluid 107 fed into pressure chamber 152 can be regulated to regulate the power of thermal engine 100. The flow rate of heat transfer fluid 135 must be regulated to determine the rate of phase change from liquid to vapor of expansion fluid 107 to expanded fluid 123. This can be done by one of two means. A first means of controlling the rate of vapor formation involves regulating the amount of expansion fluid 107 that is introduced into the pressure chamber 152. The second method is by regulating the amount of heat transfer fluid 135 that is passed through the pressure chamber 152. The rate of heat transfer and the mass flow dynamics ultimately determines the exact amount of expanded fluid 123 that is generated in pressure chamber 152 before it is introduced into intake chamber 121.

The choice of heat transfer fluid 135 is critical. Heat transfer fluid 135 cannot be combustible and should not decompose with extreme heat generated by the thermal mass 106. For example Air, Steam, Nitrogen, Helium, Argon, CO₂, and other non-combustible gases and liquids may be used. Since the heat transfer fluid 135 is circulated in a closed flow circuit, it can be pressurized to a certain degree if the heat transfer fluid tubes 137 are designed to hold the pressure. Thus, the heat transfer fluid 135 can be a pressurized gas, a refrigerant, or a liquefied cryogenic gas such as CO₂ that can have extremely good heat transfer characteristics. If it is a pressurized gas, then the heat transfer fluid tubes 137 can act as heat tubes which transfer heat by phase change, so that when the heat transfer fluid 135 is heated by the thermal mass 106 it will expand into a gas and then recondense within the pressure chamber 152 to transfer heat by phase change.

Heat transfer fluid tubes 137 can be made from durable materials with good heat transmission coefficients such as copper allows, stainless steel allows, titanium allows and platinum allows. It is preferable that the heat transfer fluid tube 137 be firmed both inside the pressure chamber 152 and within the heat transfer fluid chamber 133 to effectuate adequate heat transfer through its walls. If the pressure chamber 152 is remotely located from the thermal battery 105 then the heat transfer fluid tubes 137 must be well insulated to prevent any loss of energy to the environment. Heat transfer fluid tubes 137 should sealing pass through the walls of thermal battery vacuum chamber 131 and sealingly and fluidly connect therein to through the walls of the thermal mass chamber 132 into heat transfer fluid chamber 133. Heat transfer fluid tubes 137 should sealing pass through the walls of the pressure chamber 152 and form a suitable coil therein to maximize the exposed heat transfer area therein. No transfer of heat transfer fluid 135 should occur between the heat transfer fluid tubes 137 and the expansion fluid within the expansion chamber 122. From the pressure chamber 152 the heat transfer fluid tubes 137 connect back to the suction of the Heat transfer fluid pump 134. The output of heat transfer fluid pump 134 reconnects to heat transfer fluid tubes 137 to continue the flow of heat transfer fluid 135 back through the heat transfer fluid chamber to be recycled continuously. This way, heat transfer fluid 135 continuously serves to transfer and exchange heat between the thermal mass 106 and expansion fluid 107 inside of pressure chamber 152.

Further, the heat transfer fluid pump 134 which may be a pressure blower and must be chosen to withstand high temperatures that can be generated by charging the thermal mass 106. The exposed surface are of the heat transfer fluid tubes 137 will determine the amount of heat the heat transfer fluid 135 can transfer to expansion fluid 107 to generated expanded fluid 123. Finally the output of pressure chamber 152 sealingly and fluidly connects to intake chamber 121 through intake tube 124 to closes the loop expansion fluid and expanded fluid cycle loop through thermal engine 100.

Expansion fluid pump 138 must be a high pressure pump that can generate at least 1000 psi to overcome the pressure generated by the expanded fluid 123 inside of pressure chamber 152. An electric hydraulic pump such as a Concentric Hydraulic Pump™ made by Hadex Corporation can be used to circulate expansion fluid 107. The pump allows the exchange of heat from the heat transfer fluid 135 through the heat transfer fluid tubes 137 that pass through and within the pressure chamber 152 to uniformly heat and expand expansion fluid 107 therein from a liquid phase to an expanded fluid 123 in the vapor phase and to sealingly and fluidly transmit and accumulate pressurized expanded fluid 123 vapor into the intake chamber 121 of the engine so that when the starting means 139 turns the drive shaft 146, an expansion fluid pump 138 delivers a quantity of expansion fluid 107 into the pressure chamber 152 and further, the heat transfer fluid pump 134 blows heat transfer fluid 135 through the thermal mass chamber 132 to receive heat from the thermal mass 106 and transport it to heat transfer fluid tubes 137 in the pressure chamber 152 to exchange said heat with the expansion fluid 107 causing expansion fluid 107 to expand into a vapor and become expanded fluid 123, and when the piston head 103 is at top dead center of the cylinder chamber 140 a cylinder valve operating means 141 opens the intake valve 118 and expanded fluid 123 vapor is passed through the intake valve port 117 into the cylinder expansion chamber 108 to generate pressure and drive the piston head 103 from top dead center to bottom dead center, the piston head 103 motion generating a force transmitted by the piston crank 104 to turn the crankshaft 110 and generate mechanical power using the thermodynamic potential of the expanded fluid 123 vapor, so that when the piston head 103 is at bottom dead center the drive force generated on the drive shaft 146 causes cylinder valve operating means 141 to close the intake valve 118 and to open the exhaust valve 120 and cause expanded fluid 123 vapor to exit through exhaust valve 120 port into the exhaust chamber 122 for removal of exhaust expanded fluid 123 as the piston head 103 rises to top dead center passing expanded fluid 123 vapor into a first heat exchanger path 143 to exchange heat with the engine coolant 129 passing through a hydraulically separate second heat exchanger path 144 in the heat exchanger 127 so that the engine coolant 129 receives heat and cools and condenses the expanded fluid 123 vapor back into expansion fluid 107 and to advantageously generate a negative vapor pressure to assist and pull the piston head 103 back to top dead center to repeat the cycle.

In a conventional engine form, an exhaust camshaft 147 is axially positioned inside the exhaust chamber 122 with a cam 148 mounted thereon above each exhaust valve 120. In regular gas engines, the intake valve 118 is designed to open up when subjected to negative pressure within the cylinder expansion chamber 108. They are generally only subjected to no more than atmospheric pressure or super charger pressures. This allows gas and air mixtures to be aspirated into the cylinder expansion chamber 108. In this invention however, the intake valve 118 is designed to maintain a seal under high pressure and cannot be opened up by negative pressures within cylinder expansion chamber 108. The intake valve 118 can only be opened by the action of an intake camshaft 149 pushing the intake valve 118 open. Both intake valves 118 and exhaust valves 120 must be actuated by mechanical means only such as either a cam or a solenoid, and neither aspiration nor negative pressures should actuate either. Advantageously, both the intake valve 118 and the exhaust valve 120 form positive seals under any pressure. Thus when the intake chamber 121 is subjected to pressure from the expanded fluid 123, it forms a positive fluid seal that can only be opened by deliberate mechanical or electronic action. Most conventional engines have cams that open when their cylinder expansion chamber is subjected to negative pressure as the piston head 103 goes to bottom dead center from top dead center. This is due to the required aspiration of a four-stroke engine. Thus special care should be taken to design the intake valve 118 so that when it is at the sealing position, expanded fluid 123 will not open it by pressure alone. It is possible to increase the spring constant of the valve spring to ensure that it will have enough rest compression to withstand the pressure of the expanded fluid 123.

An intake camshaft 149 is axially positioned inside the valve block 112 with a cam 148 mounted thereon above each intake valve 118. Both cam 148 shafts are suitably mechanically attached by a drive belt 150 or gear system to a drive shaft 146 at the end of the crankshaft 110. An engine starting means 139 is also connected to drive shaft 146 to rotate the drive shaft 146 when the thermal engine 100 is started. In an electronic cylinder valve format, electric solenoids could be used to exactly open and close the intake valve 118 and exhaust valve 120 in phase with the engine cycle.

The thermal engine 100 further comprises an expansion fluid pump 138 for pumping expansion fluid 107 into the pressure chamber 152. The heat from the thermal mass 106 is transported by the heat transfer fluid 135 into the pressure chamber 152 by the expansion fluid pump 138 which delivers a quantity of expansion fluid 107 into the pressure chamber 152, and further, the heat transfer fluid pump 134 pumps heat transfer fluid 135 through the heat transfer fluid chamber 133 to receive heat from the thermal mass 106 and transport it through heat transfer fluid tubes 137 into the pressure chamber 152. Thus when the expansion fluid pump 138 pumps expansion fluid 107 into the pressure chamber 152 the heat from the heat transfer fluid 135 causes expansion fluid 107 to expand into a vapor and become expanded fluid 123. The pressure chamber 152 is sealingly and fluidly connected to the intake chamber 121 of the thermal engine 100.

Expansion fluid 107 flow is regulated to divide into two paths with a first path entering into the pressure chamber 152 to exchange heat with the heat transfer fluid 135 and to expand into expanded fluid 123 and a second path taking recirculate expansion fluid 156 back to the expansion fluid tank 145; Expanded fluid 123 generated within pressure chamber 152 directly enters into intake chamber 121, then flows therefrom into the intake valve 118 ports, which if open will have fluid communication with the cylinder expansion chamber 108 and the pressure of expanded fluid 123 will cause the piston head 103 to move from top dead center to bottom dead center and at bottom dead center will cause crankshaft 110 to rotate; and said rotation of crankshaft 110 will cause exhaust camshaft 147 to rotate and open exhaust valve 142; and said opening of exhaust valve 142 will fluidly communicate expanded fluid 123 through the exhaust valve ports 119 which fluidly communicate through the exhaust tube 125 and through the check valve 126 with either atmosphere when an open cycle design is used or with one path through a heat exchanger 127 where it is condensed back to expansion fluid 107 and then passed through the suction of the expansion fluid pump 138 and retuned partly back to the expansion fluid tank 145 and inclusively partly back to the pressure chamber 152 to be reused again to repeat the cycle as depicted in the flow circuit 700;

Yet another means of cooling expanded fluid 135 is to pass recirculate expansion fluid 156 from the bypass valve 154 through recirculate tube 155 into the interior of the exhaust tube 125 to exchange and absorb some more heat from the expanded fluid 123 in the exhaust tube 125 and to help cool expanded fluid 123 therein. Expanded fluid 123 and any condensed expansion fluid 107 can be passed through a first heat exchange path 143 of heat exchanger 127 to exchange heat with a second heat exchanger path 144 of heat exchanger 127 through which recirculated expansion fluid 156 is passed and then return condensed expanded fluid 123 as expansion fluid to the expansion fluid tank 145 to repeat the cycle.

In such a case, recirculate tube 155 must pass sealingly through the walls of the exhaust tube 125 into the interior of the exhaust tube 125 and traverses most of the length of the exhaust tube 125 to emerge therefrom hotter than its entry temperature and returns to the expansion fluid tank 145 with acquired energy from the expanded fluid 123 that would otherwise be waste. The recirculate tube 155 is preferably made from high heat conducting materials such as finned aluminum tubing or coppers tubing and can be coiled or folded internally within the exhaust tube to create a large surface area for the exchange of heat between recirculate expansion fluid 156 and expanded fluid 123. This allows maximum loss of heat from the expanded fluid 123 to the recirculate expansion fluid 156. This way most of the heat from the expanded fluid 123 is reabsorbed back into the recirculate expansion fluid 156 and not lost to atmosphere before it returns to the expansion fluid tank 145 to repeat the cycle. It is advantageous not to insulate the exhaust tube 125 so that expanded fluid 123 is condensed to expansion fluid 107 as quickly as possible. Most of the heat from the expanded fluid 123 should be absorbed by the engine block 113 from the air blown through radiator 130 and mostly by the recirculate expansion fluid 156 in heat exchanger 127 so that it can be reused as thermal energy in the thermal engine 100. The area of the heat exchanger 127 is substantial and it is calculated to suffice to condense the exhausted expanded fluid 123 before it exist heat exchanger 127. Engine coolant 129 is pumped by engine coolant pump 157 and circulated through engine block 113 and then through a radiator 130. Radiator fan 158 that blows air through the radiator 130 to remove the heat of condensation from the engine coolant 129 and reheat the outer perimeter of the engine block 113. It is advisable to insulate as much of engine block 113 as possible for maximum heat storage, but also to allow the air flow from radiator fan 158 to envelop as much of the engine block 113 to transfer as much heat thereto as possible.

Unlike conventional engines that require heat to be removed from the engine, the present invention admits to reusing the engine coolant 129's thermal energy to reheat engine block 113.

Advantageously, radiator fan 169 may be driven by either electric power from a battery or by means of the crankshaft 110 to remove heat from the radiator 130 by passing air through the radiator 130's fins and directing said air back over engine block 113 to reheat engine block 113 to a temperature close to the boiling point of the expansion fluid 107. It is important that the speed and air CFM capacity of radiator fan 169 be properly specified to remove just enough heat from engine coolant 129 and not necessarily cool engine block 113. Thus the radiator fan 169 must have a thermostat controller that activates the radiator fan 169 only when the engine coolant 129 temperatures is close to the boiling point of the expansion fluid 107. Thus minimal heat from the thermal battery 105 is lost as wasted heat to atmosphere during the operation of the thermal engine 100.

A negative pressure will be generated inside the heat exchanger 127 by the rapid condensation of the expanded fluid 123 back to expansion fluid 107 and caution must be exercised to make sure that the fluid circuits and the heat exchanger 127 can handle negative pressures.

Advantageously, the recirculate expansion fluid 156 could be directly sprayed inside of the heat exchanger 127 to mingle and condense as flowing expanded fluid 123 again. This ensures maximum use of the heat wasted from the exhausted expanded fluid 123 from the thermal engine 100. The condensed expansion fluid 107 and the recirculate expansion fluid 156 could then be returned from radiator 130 and from heat exchanger 127 to expansion tank 145.

When the engine starting means 139 turns the drive shaft 146 the expansion fluid pump 138 delivers a quantity of expansion fluid 107 through the bypass valve flow regulator into the pressure chamber 152 causing expansion fluid 107 to expand into a vapor and become expanded fluid 123; and when the piston head 103 is at top dead center of the cylinder chamber 140 the intake camshaft 149 rotates such that a cam 148 opens the intake valve 118 and expanded fluid 123 vapor is passed through the intake valve port 117 into the cylinder pressure chamber 152 to generate pressure and drive the piston head 103 from top dead center to bottom dead center, and the piston head 103 motion generates a force transmitted by the piston crank 104 to turn the crankshaft 110 and generate mechanical power using the thermodynamic potential of the expanded fluid 123 vapor; and when the piston head 103 is at bottom dead center the cylinder valve operating means 141 closes intake valves 118 and at the same time opens the exhaust valves 120 to cause expanded fluid 123 vapor to exit through exhaust valve 120 port into the exhaust chamber 122 for removal of exhaust expanded fluid 123; and as the piston head 103 rises to top dead center again pushing expanded fluid 123 vapor into the exhaust tube 125 through a check valve 126 and into the heat exchanger 127 to mingle with recirculate expansion fluid 156 and to cool and condense the expanded fluid 123 vapor back into expansion fluid 107 and to advantageously generate a negative vapor pressure to assist and pull the piston head 103 back to top dead center to repeat the cycle.

The check valve 126 prevents backflow of condensate into the exhaust chamber 122 to maintain a negative pressure and prevent condensate from entering the cylinder expansion chamber 108. Expansion fluid tank 145 receives condensed expansion fluid 107 from the heat exchanger 127 above the level of the expansion fluid 107 therein to prevent expansion fluid 107 from flooding the heat exchanger 127. In the closed cycle format of the invention, an expansion fluid pumps 138 for pumping expansion fluid 107 from the expansion fluid tank 145 into bypass valve 154 and flow regulator 159 is provided. It is not necessary for the expansion fluid pump 138 to be driven by electric power for the invention to operate, however it is important that it can be controlled to completely shut down when required even if the engine is running. If the expansion fluid pump 138 is connected to the crankshaft 110 by mechanical means an electric clutch must be used to disengage expansion fluid pump 138 it when it is required to be turned off while the thermal engine 100 is in operation. The expansion fluid 107 is then sent to the pressure chamber 152 directly to expand as expanded fluid 123 and to repeat the process.

In a conventional engine format, the intake valve 118 s and the exhaust valve 120 s ride on cam 148 s which forces them to open and close against cam springs 160's compression force in a conventional fashion. However, it is important that the both the intake valve 118 and the exhaust valve 120 be sealed by positive pressure and not aspirate as in a conventional engine.

A flywheel is attached to the drive shaft 146 and which is connected to one end of the crankshaft 110 preferably extends out of the crankcase 114 through a shaft port 162 to transmit the thermal engine 100 power in the form of torque to any desired mechanical load such as the expansion fluid pump 138 and such as engine coolant pump 157.

In the open cycle format of the present invention, the expansion fluid 107 can be delivered into the pressure chamber 152 by the expansion fluid pump 138 and also by either gravitational potential or by pressurizing the expansion fluid tank 145.

In the closed cycle format, apart from unavoidable leaks and losses, expansion fluid 107 is conserved and not lost to atmosphere as exhaust and the same quantity of expansion fluid 107 remains in the thermal engine 100 cycle in vapor and liquid phase and is reused over and over again by means of condensation and expansion. In the case of an open cycle format the expanded fluid 123 is exhausted directly from exhaust tube 125 into the atmosphere without the need for heat exchanger 127.

In general operation of the closed cycle engine, heat is generated and stored in the thermal mass 106 by one of several heating means 172. The first heating means 172 is by passing electric current through resistive heating elements 163 embedded in the thermal mass 106 for a period of time.

A second heating means 172 of thermal mass 106 is by imposing an Electromagnetic induction heating means 164 on the thermal mass 106 for a period of time.

A third heating means 172 of thermal mass 106 is by exposing the thermal mass 106 to infrared heat from infrared lamps.

A fourth heating means 172 of thermal mass 106 can be used that involves radioactive heating materials such as Thorium, 184. See FIG. 12. If Thorium 184 is used, a substantial radiation shield such as lead and carbon can be sued to shield the Thorium 184 from outside exposure. Since the shield is also a thermal mass 106, a thick layer of shielding could be incorporated enough to reduce any possible radiation from contaminating the environment. Thorium 184 is a chemical element with symbol Th and atomic number 90. Thorium was commonly used in gas mantles in the past. Thorium is used as an alloying element in non-consumable TIG welding electrodes, in high-end optics and scientific instrumentation. Thorium has a half-life of 7,340 years and melting point of 1750° C. and thus can be used as a heating source for the thermal mass 106 up to 1200° C. for an indefinite period of time. In such a case, the Thorium 184 is encased in a radioactive shield 183 such as lead. The radioactive shield 183 surrounds the Thorium 184 to effectively absorb all radiation and heat up. The radioactive shield 184 is surrounded by a substantial amount of thermal mass 106 inside of which expansion fluid 107 is introduced and expanded as expansion fluid 123.

Yet a fifth heating means 172 of thermal mass 106 is by means of a laser incorporated thereof. Electrical energy could be supplied to the laser to generate a beam that could be used to heat up the thermal mass 106.

Yet a sixth heating means 172 of thermal mass 106 is by means of introducing a chemical reaction within the heat transfer fluid chamber 133.

Yet a seventh and very important heating means 172 of thermal mass 106 is by introducing heated gases as the heat transfer fluid 135 into the heat transfer fluid tubes 137 to cause reversible heating of the thermal mass 106 by such gases acting as the heat transfer fluid 135. This can be achieved easily if the heated gas from a combustible fuel such as propane or hydrogen or Oxyhydrogen is introduced into the heat transfer fluid tubes 137 as heat transfer fluid 135. In this configuration, a hybrid mode of operation of the thermal engine 100 will incorporate a smaller horsepower conventional propane-powered, gas-powered or diesel-powered engine 800 as a back up heating means 172 when the power of the thermal battery 105 reduces. This method could also be used by generating an explosive electrolytic gas 182 generated by electrolytic cell 175 as described earlier.

The thermal energy generated by such a gas engine 800 can be used to generate exhaust heat used to heat the thermal battery 105 as well as generate heating of the pressure chamber 152 while the thermal engine is running. Further, the engine 800 can be used as a back up heat generator to allow prolonged use of the thermal engine 100 when its power dissipates. The mechanical energy of such an engine 800 can serve several purposes including generating electrical energy to reheat the thermal mass 106 over time as a heating means 172.

The engine starting means 139 starts the thermal engine 100. Preferably engine starting means 139, is an electric starter that receives electric energy from a battery and causes the drive shaft 146 to and turns a crankshaft 110. If the expansion fluid pump 138 is directly driven by the crankshaft 110, then expansion fluid pump 138 pumps a quantity of expansion fluid 107 from the expansion fluid tank 145 into the pressure chamber 152. However it is preferable that an electric expansion fluid pump 138 be used so that it can be started and turned off by the engine starting means 139. If the expansion fluid pump 138 is driven by power from crankshaft 110 then the speed of the engine can influence the speed of the expansion fluid pump 138 and the engine power can exponentially decay if it slows down and slows expansion fluid pump 138 as well. Thus, preferably, the expansion fluid pump 138 should be electric driven and made independent of the engine crankshaft 110's motion. The bypass valve 154 and the flow regulator 159 allow only the prescribed amount of expansion fluid 107 to pass into the pressure chamber 152 and the rest is returned as recirculate expansion fluid 156 through the exhaust tube 125 to the expansion fluid tank 145 by means of recirculate tube 155. It is important to note that the recirculate expansion fluid 156 need not pass through the exhaust tube 125 but can go directly into the expansion fluid tank 145. An expansion fluid tank checks valve 167 prevents any back flow from the expansion fluid tank 145 into exhaust tube 125.

The heat stored in the thermal mass 106 causes the expansion fluid 107 to expand by a phase change into expanded fluid 123 to generate pressure in the pressure chamber 152 and ultimately in the intake chamber 121.

In the closed format of the invention, the heat exchanger 127 cools the expanded fluid 123 vapors back into expansion fluid 107 by using the engine coolant 129 to cool the vapor. A check valve 126 at the end of the exhaust tube 125 causes a vacuum within the exhaust chamber 122 as the expanded fluid 123 condenses to expansion fluid 107. This vacuum is generated in the exhaust tube 125 and transmitted to the cylinder expansion chamber 108 and this increases the power of the thermal engine 100 since when the exhaust valve ports 119 open, the negative pressure in the cylinder expansion chamber 108 will in addition to the energy stored in the flywheel, cause the piston head 103 to rapidly return by negative pressure to top dead center position. This adds more power to the thermal engine 100 since the invention essentially teaches the use of expansion fluid 107 in both its pressurized vapor expanded fluid 123 form and its vacuum condensate state to push and return the piston head 103 from top dead center position to bottom dead center position and back to top dead center position. This vacuum assistance is possible in both the open cycle format and the closed cycle format if the exhausted expanded fluid 123 is passed through a long enough exhaust tube 125 before being exhausted to atmosphere. In such a case, the rapid cooling of the expanded fluid 123 in the exhaust tube 125 causes the expanded fluid 123 to undergo a phase change from the vapor phase to the liquid phase and such rapid condensation results in a vacuum being generated momentarily in the cylinder expansion chamber 108. Thus, by adjusting the length of the exhaust tube 125, it is possible to regulate the timing of the vacuum formed with the motion of the piston head 103 as moves from top dead position center to bottom dead center position and then back to top dead center position.

At close to bottom dead center the turning of the crankshaft 110, the momentum stored in the flywheel 161, and the negative pressure of vapor condensation causes the piston head 103 to rapidly move back towards top dead center to repeat the cycle and to a position that causes intake valve 118 close while causing the exhaust valve 120 to open. In a closed cycle format of the invention, the pressurized expanded fluid 123 in the cylinder expansion chamber 108 is pushed through the exhaust valve ports 119 into the exhaust chamber 122, allowing the expanded fluid 123 to exit the cylinder expansion chamber 108 through the exhaust tube 125 and check valve 126 into the heat exchanger 127. Alternatively the expanded fluid 123 can exit the cylinder expansion chamber 108 and be expelled directly to atmosphere through the exhaust tube 125 and check valve 126 to bypass the heat exchanger 127. The piston head 103 freely returns to top dead center by the continued angular momentum from the rotation of the crankshaft 110 and flywheel 161 allowing the remaining elements of the expanded fluid 123 out of the cylinder expansion chamber 108 into the exhaust chamber 122 and then to cool either in the exhaust tube 125 or in the heat exchanger 127 to and generate a negative pressure of vapor condensation so that the cycle can continuously repeat until stopped. To stop the cycle, the bypass valve 154 simply bypasses expansion fluid 107 through to the recirculate tube 155 and closes off the flow to the pressure chamber 152 to stop the flow of expansion fluid 107 into the pressure chamber 152.

The thermal mass 106 can be constructed with multiple layers of metal slabs so that it is easier to handle and easier to conform to the space requirements of a conventional vehicle 300. In fact the thermal mass 106 can be made completely from sintered metals that can be made to conform to any desired shape. In one preferred embodiment, the thermal mass 106 is constructed from layers of metal slabs which form a stack with passages and openings to form the heat transfer fluid chamber 133 needed for the embedded heating means 172 and to allow heat transfer fluid 135 to freely and evenly flow through the entire surfaces of the thermal mass 106 to effectuate adequate heat transfer to the heat transfer fluid 135.

The thermal mass 106 can be made from a single casting with all the required passages already configured within it for the heat transfer fluid 135 and the heating means 172. Adequate thermal insulation should surround the thermal battery vacuum chamber 131 to insulate and prevent loss of heat energy to the environment. Since most insulation is also porous to fluids, the entire volume of the heat transfer fluid chamber 133 can be filled with insulation. Preferably, the thermal insulation is made from such as polyamides and ceramics fiber materials that can withstand extremely high temperatures. Such materials are available as wrap around tapes from companies such as engineered Tapes Inc., and ABS thermal Technologies in New York. The thermal mass 106 is preferably made from stainless steel and metal alloys, but can also be made from ceramics, silicates, clays or carbon compounds. Preferably a dense material with a high heat storage capacity should be used to achieve a high storage heat capacity in the thermal mass 106. The heat energy, q, stored in a material of mass m, is proportional to the temperature difference, dt, it undergoes and its specific heat capacity c_(p) as given by the formula:

Q=mc _(p) dt

Such dense materials that may be used for a thermal mass 106 include iron, lead, stainless steel, titanium, aluminum, molten salts, carbon composites, fiberglass composites and ceramics. The heat energy storage density is a function of the density of the material since the mass is a function of the density. Examples of the heat storage density of some materials are shown in the table below:

heat storage density Operating temperature Material Kj/m²° C. range, ° C. Aluminum 2484 680 Cast Iron, 3889 1151 Stainless Steel, Ceramics 2800 2000 Taconite 2500 2000 Saltstream ™ 565 1960 565

The expansion fluid tank 145 should be made from durable rust resistant, pressure resistant and heat resistant materials such as Aluminum, Stainless steel, titanium, platinum, copper, graphite, and other suitable materials. Since the expansion fluid tank 145 can be pressurized in some instances, it must be designed to hold adequate pressure above 500 psi and its construction should follow adequate guidelines for manufacture of pressure tanks of the required pressure ratings.

The engine block 113 and engine components can be constructed from metal alloys commonly used in the manufacture of standard combustion engines. However since the thermal loads that the thermal engine 100 is subjected to can be far less that regular combustion engines, it is possible to construct the engine components from aluminum alloys, ceramics, plastics and even carbon fiber materials. If water is used as an expansion fluid, it is even possible to manufacture the engine and its components using high temperature engineering plastics such as mentioned earlier. The design of the cylinders 101, pistons 102 and other components could be augmented by inserting adequate support materials and coatings such as stainless steel sleeves to prevent the wear due to the friction of the piston head 103 sliding on the cylinder 101 walls. Advantageously, the use of engineering plastics could make the thermal engine 100 as light as possible to compensate for the additional weight that is needed for the thermal battery 105. Some other components of the thermal engine 100 could also be made from adequate engineered plastics that can withstand mechanical loads and heat. In all the cost of manufacture of the thermal engine 100 can be reduced considerably by a suitable choice of materials.

The engine is a two-stroke engine and unlike a four-stroke engine, compressed-air acting can start the thermal engine 100 as the engine starting means 139. The starting of the thermal engine 100 power cycle causes the expansion fluid pump 138 to deliver a quantity of expansion fluid 107 through the bypass valve 154 into the pressure chamber 152 and the heat stored in the thermal mass 106 causes the expansion fluid 107 to become heated and to undergo a phase change and become an expanded fluid 123 vapor within the pressure chamber 152.

It is important that the intake chamber 121 be insulated as much as possible so that the expanded fluid 123 vapor retains as much heat as possible before it is introduced into the cylinder expansion chamber 108. It is important that the exhaust chamber 122 not be insulated so that as much heat can be taken out of the expanded fluid 123 vapors to reduce it to expansion fluid 107 liquid after it has done its work.

The thermal engine 100 preferably operates on a noncombustible expansion fluid 107 such as water or a refrigerant fluid; it is important that the expansion fluid 107 have as high a heat of vaporization as possible. Water and refrigerants such as ammonia have the highest heat of vaporization per kilogram. Some examples of heat of vaporization are given below:

Heat of vaporization Heat of vaporization Compound (Kj mol⁻¹) (Kj kg⁻¹) Methane 8.19 760 Ethanol 38.6 841 Methanol 35.3 1104 Ammonia 23.35 1371 Water 40.65 2257

The thermal energy that causes expansion fluid 107 to expand to expand fluid can be directly transferred by direct contact of the expansion fluid 107 with the surface of the thermal mass 106, however caution must be applied since this can cause rapid elevated and uncontrollable pressures. However it is quite possible to use the thermal mass 106 to directly heat the expansion fluid 107 by controlling the amount of expanded fluid 123 one exposes to the thermal mass 106 for a given period of time. However uneven distribution across the thermal mass 106 of expansion fluid 107 can cause localized cooling of the thermal mass 106 and a reduction in efficiency and power. Also superheating of the expansion fluid 107 can occur in which case a lot of energy will be wasted and never recovered. Thus it is advantageous to use a suitable heat transfer fluid 135 such as Air, Nitrogen, CO₂, Steam and Helium, to effectuate even and efficient transfer of heat energy from the thermal mass 106 to the expansion fluid 107 through the pressure chamber 152.

The expansion fluid pump 138 supplies expansion fluid 107 from the expansion tank to the pressure chamber 152 so that when the expansion fluid 107 enters the pressure chamber 152 it absorbs heat from the heat transfer fluid 135 and it expands quickly and pressurizes the pressure chamber 152 with uniform vapor pressure. This way the vapor pressure is constantly transmitted from the pressure chamber 152 to intake valve 118 and so the pressure is readily available to power the thermal engine 100. Thus unlike conventional engines, the intake chamber 121 is always under pressure and all the intake valve 118 s are subjected to this constant pressure so that when each opens it is fed pressurized expanded fluid 123 directly. In this way, there is very little fluid regulation needed to ensure adequate operation of the thermal engine 100.

In accordance with the present invention, a thermally charged thermal engine 100 is used to generate mechanical energy by a phase change of a liquid such as water to a gas. The thermal energy causes the expansion fluid 107 to expand into a gas by a phase change and thus permits the thermal engine 100 to run like a conventional engine without much change to the engine configuration.

An objective of the prevent invention is to provide a thermal engine 100 which can be operated with an expansion fluid 107 having the most suitable thermodynamic properties to achieve a high degree of efficiency during operation. An engine of this kind, in accordance with the invention, can be optimized by its geometry through maximizing the thermal mass 106 and minimizing the surface area of the thermal battery 105 for storing a maximum amount of thermal energy in the form of a direct heat.

Essentially, a heat storing thermal battery 105 is incorporated into the thermal engine 100 to permit energy to be stored thermally instead of chemically as in the case of a conventional electric battery. Advantageously, the entire engine block 113 can be used as a thermal source in the form of a thermal mass 106, so that a large amount of thermal energy can be stored for later use. The thermal battery 105 can be charged with heat to a high temperature using electric heaters, electromagnetic induction heaters or other forms of heat generators incorporated thereof. For example, a solar powered heat generator such as a lens can be used to focus heat on the thermal mass during charging to reduce the cost of using conventional electric energy sources. In the case when a fluid can undergo a phase change with very little heat, it is possible to use very low temperature thermal heating means 172 to store energy in a thermal battery 105. It is possible that with the advances in nuclear technology that a miniscule and well-protected thermonuclear heating means such as Thorium 184 could be incorporated into a well-protected radiation shielded thermal battery 105. In case of emergencies, it is possible to use a chemically based heating fuel to generate heat that can be stored in the thermal battery 105.

Moreover, the exhaust from the thermally expanded fluid 123 from the thermal engine 100 can be cooled to generate a reverse condensation liquid phase vacuum that could assist in the return cycle by pulling on the piston head 103 when it is at top bottom center. In such a case, the maximum potential of the expansion fluid 107 during condensation and creating a vacuum could be used in conjunction with its expansive energy. An expansion fluid 107 such as water can be injected into the thermal mass 106 of the thermal engine 100 to generate steam and power the thermal engine 100. Optionally, a combination of water and ethanol and other fluids may be used as an expansion fluid. Advantageously, much more energy can be stored in such a thermal battery 105 than in a conventional electric battery of the same weight. This can be demonstrated by simply exhausting the electrical energy of an electric battery of a given mass to heat up a thermal mass 106 of the same mass.

The thermal battery vacuum chamber 131 must be designed to maximally surround the thermal mass 106 so that no heat can be transmitted by conduction or convection from the thermal mass 106 to the thermal battery vacuum case 131 by conduction or convection. Where possible, the conductive portions where the thermal mass 106 contacts the thermal battery vacuum case 131 should be minimized so that the thermal mass 106 is essentially suspended inside the thermal battery vacuum chamber 131 by minimally conductive members. A vacuum resistant material should be used to construct the thermal battery vacuum case 131 to prevent the loss of vacuum, thus preferably the thermal battery vacuum case 131 could be made from a metal alloy of suitable properties. The outer thermal insulation of the thermal battery vacuum case 131 should be designed for minimal radiation. Preferably, the interior wall of the thermal battery vacuum chamber 131 should be reflective to heat so that radiation is stored inside of it by reflection with minimal losses. Thermal battery vacuum case 131 could be made from thermally insulating materials so that as much heat is stored within as possible. The thermal battery vacuum chamber 131 should be evacuated to a high degree to avoid heat loss during operation. All fluid delivery passages and tubes should be insulated to a very high degree to prevent heat loss and their lengths should be minimized within as much as possible.

Since there is no need to compress a fluid for firing and combustion, all the engines should be designed as two stroke engines, with a single stroke for a power stroke and a single return stroke for an exhaust stroke. In the preferred embodiment, pressurized expanded fluid 123 enters the intake chamber 121 and serves all the cylinder expansion chambers 108 simultaneously. This reduces the complexity of the expanded fluid 123 control system since the expanded fluid 123 inside the intake chamber 121 is always pressurized during operation and ready to feed pressurized expanded fluid 123 into each cylinder expansion chamber 108 when its intake valve 118 opens. Each intake valve 118 opens when its piston head 103 is at its top dead center and again closes when its piston head 103 is at bottom dead center. Each exhaust valve 120 opens when its piston head 103 is at its bottom dead center and again closes when its piston head 103 is at top dead center. The exact position when the valves open could be adjusted to compensate for lag in the delivery rate of the expanded fluid 123 and the exhausted rate of the expanded fluid 123. In some cases, it is possible to isolate each cylinder head 109 to have its own intake chamber 121 and its own exhaust chamber 122. In such a case it is possible to rearrange the power strokes of each piston head 103 so that they can be sequenced as necessary to maximize the power outtake of the thermal engine 100. For example, unlike a gas engine or diesel engine which relies on a sudden explosion to generate pressure, the exhaust from a first piston of the thermal engine 100 could be channeled to a second piston and from thence to a third and so on. This way the maximum expansion of the expanded fluid 123 is achieved.

A flywheel is essential to keep the cycle going since very little power is generated during the motion of the piston head 103 from bottom dead center to top dead center even though if a vacuum is maintained in the exhaust chamber 122 a substance force could be generated to assist the return of the piston head 103. In the case when a closed cycle thermal engine 100 is built the exhausted expanded fluid 123 vapor should be cooled in a non-resistive heat exchanger 127. The passageways for the expanded fluid 123 vapor in the heat exchanger 127 should be free from any back pressure and the heat exchanger 127 should be able to quickly remove all the heat of condensation from the expanded fluid 123 so that it can quickly condense to expansion fluid 107 and thus recycled as quickly as possible before losing most of its heat. In fact the heat removed by engine coolant 129 passing through the heat exchanger 127 should be equal or more than the heat of condensation of the expanded fluid 123 so that the liquid phase of the expansion fluid 107 remains as close to its boiling point as possible. This ensures that very little heat is taken from the thermal mass 106 by the expansion fluid 107 to re-expand it to a vapor phase. The expansion fluid tank 145 could also be incorporated as part of the heat exchanger 127. This way the expansion fluid 107 is stored in the heat exchanger 127 as opposed to using a separate expansion fluid tank 145 for the same purpose. The condensate expansion fluid 107 from the heat exchanger 127 can be held in a segment of heat exchanger 127, which will act as an expansion fluid tank 145 to minimize the size and complexity of the thermal engine 100, and more importantly to minimize the exposure of the condensed expansion fluid 107 to the atmosphere. The expansion fluid 107 from the expansion fluid tank 145 can then be transferred directly by the expansion fluid pump 138 to the pressure chamber 152 for immediate reuse as needed. If the heat exchanger 127 is large enough, the condensate could be taken directly from the heat exchanger 127 output and reused as the expansion fluid 107 so that it can act directly as the expansion fluid tank 145.

In the case when an open cycle thermal engine 100 is built the exhausted expanded fluid 123 vapor could be exhausted directly to the atmosphere and not reused. The most suitable expansion fluid 107 for this purpose is water since it is environmentally friendly. In the open cycle format of the invention, the thermal engine 100 is provided with an expansion fluid tank 145 that can store an adequate amount of expansion fluid 107 for the required period of use of the thermal engine 100. Then, the exhausted expanded fluid 123 could be passed through the heat exchanger 127 or simply expelled to atmosphere as vapor. Preferably, the heat exchanger 127 can be a parallel plate heat exchanger with alternating plates separating passages for the engine coolant 129 and the expanded fluid 123 and recirculate expansion fluid respectively. It could also be made from a simple coiled tube-in-tube that could be incorporated with a check valve 126 at its end that only allows fluids to pass to atmospheric pressure so that as the expanded fluid 123 is exhausted it cools inside the exhaust tube 125 and condenses to a liquid phase to form a vacuum in the exhaust tube 125 and the exhaust chamber 122 and the check valve 126 closes to maintain the vacuum. The vacuum subjects the exhaust valve 120 to a negative pressure that can be used to assist the piston head 103 to rise to top dead center when the said exhaust valve 120 is opened. When the vacuum subsides during the power cycle, the check valve 126 relaxes and opens and expansion fluid 107 is expelled into the atmosphere. This way, only liquid is exhausted as a wasted fluid from the engine. No heat exchanger 127 may be needed if there is an adequate supply of expansion fluid, but reusing the expansion fluid 107 can assist in reducing the energy drawn from the thermal mass 106. In such a case, the condensed expansion fluid 107 can be recaptured in the expansion fluid tank 145 under atmospheric conditions. In the open cycle embodiment of the present invention, the expansion fluid tank 145 should be in fluid communication with the atmosphere so that no back pressure is generated by the exhausting expanded fluid 123, and if the heat exchanger 127 becomes too hot, the expanded fluid 123 vapor can simply escape from expansion fluid tank 145 to atmosphere without generating a back pressure on the intake chamber. In yet another embodiment of the open cycle, the heat exchanger 127 could be submerged inside the expansion fluid 107 in the expansion fluid tank 145 to exchange heat directly with the expansion fluid 107 stored therein. This allows a lot of the exhaust heat to be captured. However if this is done it is important that the output of the heat exchanger 127 exhaust be above the liquid level so that in the case of a vacuum being generated by the condensate, the expansion fluid 107 will not be sucked backwards into the exhaust chamber 122.

While the invention can be used only with a noncombustible phase change liquid such as water it may also be used in combination with or separately with a potentially combustible expansion fluid 107 that have a high expansion value.

In the attached Figures, the following flow paths are designated with the following part numbers: coolant flow path 400, expanded fluid flow path 500, and heat transfer fluid flow path 600. The following system parts and part numbers are also illustrated: heating elements 163, thermal insulation 166 and output shaft 170.

While the invention has been described, disclosed, illustrated and shown in various terms or certain embodiments or modifications which it has assumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended. 

I claim as my invention:
 1. A thermal engine, comprising: an electrolytic cell containing an anode and a cathode and being connected to an electric power source; an engine block fluidly connected to said electrolytic cell and including a cylinder and a piston slidably retained within said cylinder to define an expansion chamber and including an intake chamber and an exhaust chamber; a heat exchanger fluidly connected to said engine block; said heat exchanger being fluidly connected to an expansion fluid tank; and an expansion fluid pump being fluidly connected to said expansion fluid tank; wherein said expansion fluid pump is fluidly connected to said electrolytic cell; said electrolytic cell, said engine block, said heat exchanger and said expansion fluid pump together defining a looped fluid flow path; such that said expansion fluid pump propels water from said expansion fluid tank into said electrolytic cell, which generates a quantity of oxyhydrogen from the water; and propels said oxyhydrogen into one of said expansion chamber and said exhaust chamber, whereupon oxyhydrogen propelled into said intake chamber and said expansion chamber expands abruptly into steam in said expansion chamber to increase pressure within said expansion chamber and thereby enhance thermal engine power, and oxyhydrogen propelled into said heat exchanger cools the water vapor back into liquid water, which generates a vacuum within said exhaust chamber to increase the power of the thermal engine.
 2. A thermal engine comprising: an engine block fluidly connected to an electrolytic cell and including a cylinder and a piston slidably retained within a cylinder to define an expansion chamber and including an intake chamber and an exhaust chamber. 